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Search: a326801 -id:a326801
Displaying 1-5 of 5 results found. page 1
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A326551 E.g.f. C(x), where C(x*y) + i*S(x*y) = exp( i*Integral Integral C(x*y) dx dy ) such that C(x)^2 + S(x)^2 = 1. +10
9
1, -2, 56, -8336, 3985792, -4679517952, 11427218287616, -51793067942397952, 400951893341645930496, -4975999084909976839454720, 94178912073481319162642169856, -2610878440961060713599511173791744, 102545703927828194073741484514193965056, -5548919569628098800740786379865766154469376, 403949193167852851803947801218003477783686152192 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
COMMENTS
The hyperbolic analog of the e.g.f. is described by A325291.
The e.g.f. can be derived from the functions described by A326797, A326798, and A326799.
The e.g.f. can be derived from the functions described by A326800, A326801, and A326802.
LINKS
FORMULA
E.g.f. C(x) = Sum_{n>=0} a(n)*x^(2*n)/(2*n)!^2, where series C(x) and related series S(x) satisfy the following relations.
(1.a) C(x)^2 + S(x)^2 = 1.
(1.b) S'(x)/C(x) = -C'(x)/S(x) = 1/x * Integral C(x) dx.
(2.a) S(x) = Integral C(x)/x * (Integral C(x) dx) dx.
(2.b) C(x) = 1 - Integral S(x)/x * (Integral C(x) dx) dx.
(3.a) C(x) + i*S(x) = exp( i*Integral 1/x * (Integral C(x) dx) dx ).
(3.b) C(x) = cos( Integral 1/x * (Integral C(x) dx) dx ).
(3.c) S(x) = sin( Integral 1/x * (Integral C(x) dx) dx ).
Integration.
(4.a) S(x*y) = Integral C(x*y) * (Integral C(x*y) dy) dx.
(4.b) C(x*y) = 1 - Integral S(x*y) * (Integral C(x*y) dy) dx.
(4.c) S(x*y) = Integral C(x*y) * (Integral C(x*y) dx) dy.
(4.d) C(x*y) = 1 - Integral S(x*y) * (Integral C(x*y) dx) dy.
Exponential.
(5.a) C(x*y) + i*S(x*y) = exp( i*Integral Integral C(x*y) dx dy ).
(5.b) C(x*y) = cos( Integral Integral C(x*y) dx dy ).
(5.c) S(x*y) = sin( Integral Integral C(x*y) dx dy ).
Derivatives.
(6.a) d/dx S(x*y) = C(x*y) * Integral C(x*y) dy.
(6.b) d/dx C(x*y) = -S(x*y) * Integral C(x*y) dy.
(6.c) d/dy S(x*y) = C(x*y) * Integral C(x*y) dx.
(6.d) d/dy C(x*y) = -S(x*y) * Integral C(x*y) dx.
EXAMPLE
E.g.f. C(x) = 1 - 2*x^2/2!^2 + 56*x^4/4!^2 - 8336*x^6/6!^2 + 3985792*x^8/8!^2 - 4679517952*x^10/10!^2 + 11427218287616*x^12/12!^2 - 51793067942397952*x^14/14!^2 + 400951893341645930496*x^16/16!^2 - 4975999084909976839454720*x^18/18!^2 + 94178912073481319162642169856*x^20/20!^2 -+ ...
where C(x) = cos( Integral 1/x * (Integral C(x) dx) dx ),
also, C(x*y) = cos( Integral Integral C(x*y) dx dy ).
RELATED SERIES.
S(x) = x - 8*x^3/3!^2 + 576*x^5/5!^2 - 160768*x^7/7!^2 + 123535360*x^9/9!^2 - 212713734144*x^11/11!^2 + 716196297048064*x^13/13!^2 - 4280584942657732608*x^15/15!^2 + 42250703121584165486592*x^17/17!^2 - 651154631135458759089848320*x^19/19!^2 + 14983590319172065236171175755776*x^21/21!^2 -+ ...
where S(x) = sin( Integral 1/x * (Integral C(x) dx) dx ),
also, S(x*y) = sin( Integral Integral C(x*y) dx dy ),
such that C(x)^2 + S(x)^2 = 1.
PROG
(PARI)
{a(n) = my(C=1, S=x); for(i=1, 2*n,
S = intformal( C/x * intformal( C +x*O(x^(2*n)) ) );
C = 1 - intformal( S/x * intformal( C +x*O(x^(2*n)) ) ); ); (2*n)!^2*polcoeff(C, 2*n)}
for(n=0, 30, print1(a(n), ", "))
CROSSREFS
Cf. A326552, A325291, A326556 (C^2).
KEYWORD
sign
AUTHOR
Paul D. Hanna, Jul 25 2019
STATUS
approved
A326552 E.g.f. S(x), where C(x*y) + iS(x*y) = exp( i*Integral Integral C(x*y) dx dy ) such that C(x)^2 + S(x)^2 = 1. +10
8
1, -8, 576, -160768, 123535360, -212713734144, 716196297048064, -4280584942657732608, 42250703121584165486592, -651154631135458759089848320, 14983590319172065236171175755776, -496301942561421311900528265903734784, 22953613919171561374366988621726483480576, -1444609513446024762131466039751756562435145728, 121022534222796916421149671221445519229890299166720 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
The hyperbolic analog of the e.g.f. is described by A325292.
The e.g.f. can be derived from the functions described by A326797, A326798, and A326799.
The e.g.f. can be derived from the functions described by A326800, A326801, and A326802.
LINKS
FORMULA
E.g.f. S(x) = Sum_{n>=0} a(n)*x^(2*n+1)/(2*n+1)!^2, where series S(x) and related series C(x) satisfy the following relations.
(1.a) C(x)^2 + S(x)^2 = 1.
(1.b) S'(x)/C(x) = -C'(x)/S(x) = 1/x * Integral C(x) dx.
(2.a) S(x) = Integral C(x)/x * (Integral C(x) dx) dx.
(2.b) C(x) = 1 - Integral S(x)/x * (Integral C(x) dx) dx.
(3.a) C(x) + i*S(x) = exp( i*Integral 1/x * (Integral C(x) dx) dx ).
(3.b) C(x) = cos( Integral 1/x * (Integral C(x) dx) dx ).
(3.c) S(x) = sin( Integral 1/x * (Integral C(x) dx) dx ).
Integration.
(4.a) S(x*y) = Integral C(x*y) * (Integral C(x*y) dy) dx.
(4.b) C(x*y) = 1 - Integral S(x*y) * (Integral C(x*y) dy) dx.
(4.c) S(x*y) = Integral C(x*y) * (Integral C(x*y) dx) dy.
(4.d) C(x*y) = 1 - Integral S(x*y) * (Integral C(x*y) dx) dy.
Exponential.
(5.a) C(x*y) + i*S(x*y) = exp( i*Integral Integral C(x*y) dx dy ).
(5.b) C(x*y) = cos( Integral Integral C(x*y) dx dy ).
(5.c) S(x*y) = sin( Integral Integral C(x*y) dx dy ).
Derivatives.
(6.a) d/dx S(x*y) = C(x*y) * Integral C(x*y) dy.
(6.b) d/dx C(x*y) = -S(x*y) * Integral C(x*y) dy.
(6.c) d/dy S(x*y) = C(x*y) * Integral C(x*y) dx.
(6.d) d/dy C(x*y) = -S(x*y) * Integral C(x*y) dx.
EXAMPLE
E.g.f. S(x) = x - 8*x^3/3!^2 + 576*x^5/5!^2 - 160768*x^7/7!^2 + 123535360*x^9/9!^2 - 212713734144*x^11/11!^2 + 716196297048064*x^13/13!^2 - 4280584942657732608*x^15/15!^2 + 42250703121584165486592*x^17/17!^2 - 651154631135458759089848320*x^19/19!^2 + 14983590319172065236171175755776*x^21/21!^2 -+ ...
where S(x) = sin( Integral 1/x * (Integral C(x) dx) dx ),
also, S(x*y) = sin( Integral Integral C(x*y) dx dy ),
such that C(x)^2 + S(x)^2 = 1.
RELATED SERIES.
C(x) = 1 - 2*x^2/2!^2 + 56*x^4/4!^2 - 8336*x^6/6!^2 + 3985792*x^8/8!^2 - 4679517952*x^10/10!^2 + 11427218287616*x^12/12!^2 - 51793067942397952*x^14/14!^2 + 400951893341645930496*x^16/16!^2 - 4975999084909976839454720*x^18/18!^2 + 94178912073481319162642169856*x^20/20!^2 -+ ...
where C(x) = cos( Integral 1/x * (Integral C(x) dx) dx ),
also, C(x*y) = cos( Integral Integral C(x*y) dx dy ).
RELATED FUNCTIONS.
Given functions Ax, Bx, Cx, Ay, By, and Cy defined by
(1a) Ax = 0 + Integral Bx*Cy - Cx*By dx,
(1b) Bx = 1 + Integral Cx*Ay - Ax*Cy dx,
(1c) Cx = 0 + Integral Ax*By - Bx*Ay dx,
(2a) Ay = 0 + Integral By*Cx - Cy*Bx dy,
(2b) By = 0 + Integral Cy*Ax - Ay*Cx dy,
(2c) Cy = 1 + Integral Ay*Bx - By*Ax dy,
then
S(x*y) = Ax*Ay + Bx*By + Cx*Cy.
These related series begin as follows.
Ax = x + (-1*x^3 - 3*x*y^2)/3! + (1*x^5 - 30*x^3*y^2 + 5*x*y^4)/5! + (-1*x^7 + 315*x^5*y^2 + 525*x^3*y^4 - 7*x*y^6)/7! + (1*x^9 - 1260*x^7*y^2 + 18270*x^5*y^4 - 2940*x^3*y^6 + 9*x*y^8)/9! + (-1*x^11 + 3465*x^9*y^2 - 496650*x^7*y^4 - 695310*x^5*y^6 + 10395*x^3*y^8 - 11*x*y^10)/11! + ... (A326797)
Bx = 1 + (-1*x^2)/2! + (1*x^4)/4! + (-1*x^6 + 120*x^4*y^2)/6! + (1*x^8 - 672*x^6*y^2)/8! + (-1*x^10 + 2160*x^8*y^2 - 120960*x^6*y^4)/10! + (1*x^12 - 5280*x^10*y^2 + 1584000*x^8*y^4)/12! + ... (A326798)
Cx = (2*x*y)/2! + (-4*x*y^3)/4! + (-160*x^3*y^3 + 6*x*y^5)/6! + (1344*x^3*y^5 - 8*x*y^7)/8! + (145152*x^5*y^5 - 5760*x^3*y^7 + 10*x*y^9)/10! + (-2534400*x^5*y^7 + 17600*x^3*y^9 - 12*x*y^11)/12! + ... (A326799)
Ay = -y + (3*x^2*y + 1*y^3)/3! + (-5*x^4*y + 30*x^2*y^3 + -1*y^5)/5! + (7*x^6*y + -525*x^4*y^3 + -315*x^2*y^5 + 1*y^7)/7! + (-9*x^8*y + 2940*x^6*y^3 + -18270*x^4*y^5 + 1260*x^2*y^7 + -1*y^9)/9! + (11*x^10*y + -10395*x^8*y^3 + 695310*x^6*y^5 + 496650*x^4*y^7 + -3465*x^2*y^9 + 1*y^11)/11! + ...
By = (2*x*y)/2! + (-4*x^3*y)/4! + (6*x^5*y + -160*x^3*y^3)/6! + (-8*x^7*y + 1344*x^5*y^3)/8! + (10*x^9*y + -5760*x^7*y^3 + 145152*x^5*y^5)/10! + (-12*x^11*y + 17600*x^9*y^3 + -2534400*x^7*y^5)/12! + ...
Cy = 1 + (-1*y^2)/2! + (1*y^4)/4! + (120*x^2*y^4 + -1*y^6)/6! + (-672*x^2*y^6 + 1*y^8)/8! + (-120960*x^4*y^6 + 2160*x^2*y^8 + -1*y^10)/10! + (1584000*x^4*y^8 + -5280*x^2*y^10 + 1*y^12)/12! + ...
PROG
(PARI) {a(n) = my(C=1, S=x); for(i=1, 2*n+1,
S = intformal( C/x * intformal( C +x*O(x^(2*n+1)) ) );
C = 1 - intformal( S/x * intformal( C +x*O(x^(2*n+1)) ) ); ); (2*n+1)!^2*polcoeff(S, 2*n+1)}
for(n=0, 30, print1(a(n), ", "))
CROSSREFS
KEYWORD
sign
AUTHOR
Paul D. Hanna, Jul 25 2019
STATUS
approved
A326800 Consider the e.g.f. S(x,y) = Sum_{n>=0} Sum_{k=0..n} T(n,k) * x^(2*n-2*k+1) * y^(2*k) / ((2*n-2*k+1)!*(2*k)!) and related functions C(x,y) and D(x,y), as defined in the Formula section. Sequence gives the triangular array of coefficients T(n,k) (n>=0, 0<=k<=n) of S(x,y). +10
8
1, -1, -1, 1, -3, 1, -1, 15, 15, -1, 1, -35, 145, -35, 1, -1, 63, -1505, -1505, 63, -1, 1, -99, 5985, -30387, 5985, -99, 1, -1, 143, -16401, 539679, 539679, -16401, 143, -1, 1, -195, 36465, -3275811, 18679617, -3275811, 36465, -195, 1, -1, 255, -70785, 12723711, -506849409, -506849409, 12723711, -70785, 255, -1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET
1,5
COMMENTS
The e.g.f. S(x,y) is equivalent to the e.g.f. of A326797.
LINKS
Paul D. Hanna, Table of n, a(n) for n = 1..1891 (first 61 rows of this triangle).
FORMULA
The e.g.f. Sx = S(x,y) and related functions Cx = C(x,y), Dx = D(x,y), Sy = S(y,x), Cy = C(y,x), and Dy = D(y,x) satisfy the following relations.
DEFINITION.
(1a) Sx = Integral Cx*Dy + Cy*Dx dx,
(1b) Cx = sqrt(1/2) - Integral Sx*Dy + Sy*Dx dx,
(1c) Dx = sqrt(1/2) - Integral Sx*Cy - Sy*Cx dx,
(2a) Sy = Integral Cy*Dx + Cx*Dy dy,
(2b) Cy = sqrt(1/2) - Integral Sy*Dx + Sx*Dy dy,
(2c) Dy = sqrt(1/2) - Integral Sy*Cx - Sx*Cy dy.
IDENTITIES.
(3a) Dx^2 + Cx^2 + Sx^2 = 1.
(3b) Dy^2 + Cy^2 + Sy^2 = 1.
(4a) Dx*(d/dx Dx) + Cx*(d/dx Cx) + Sx*(d/dx Sx) = 0.
(4b) Dy*(d/dy Dy) + Cy*(d/dy Cy) + Sy*(d/dy Sy) = 0.
(4c) Dy*(d/dx Dx) - Cy*(d/dx Cx) - Sy*(d/dx Sx) = 0.
(4d) Dx*(d/dy Dy) - Cx*(d/dy Cy) - Sx*(d/dy Sy) = 0.
(5a) (Dx*Dy - Cx*Cy - Sx*Sy)^2 + (d/dx Dx)^2 + (d/dx Cx)^2 + (d/dx Sx)^2 = 1.
(5b) (Dx*Dy - Cx*Cy - Sx*Sy)^2 + (d/dy Dy)^2 + (d/dy Cy)^2 + (d/dy Sy)^2 = 1.
RELATED FUNCTIONS.
(6a) SS(x*y) = Dx*Dy - Cx*Cy - Sx*Sy.
(6b) d/dx SS(x*y) = Dx*(d/dx Dy) - Cx*(d/dx Cy) - Sx*(d/dx Sy).
(6c) d/dy SS(x*y) = Dy*(d/dy Dx) - Cy*(d/dy Cx) - Sy*(d/dy Sx).
(7a) CC(x*y)^2 = (Cx*Dy + Cy*Dx)^2 + (Sx*Dy + Sy*Dx)^2 + (Sx*Cy - Sy*Cx)^2.
(7b) CC(x*y)^2 = (d/dx Dx)^2 + (d/dx Cx)^2 + (d/dx Sx)^2.
(7c) CC(x*y)^2 = (d/dy Dy)^2 + (d/dy Cy)^2 + (d/dy Sy)^2.
In the above, CC(x) and SS(x) are the e.g.f.s of A326551 and A326552 defined by
(8a) CC(x*y)^2 + SS(x*y)^2 = 1,
(8b) SS(x*y) = Integral CC(x*y) * (Integral CC(x*y) dy) dx,
(8c) CC(x*y) = 1 - Integral SS(x*y) * (Integral CC(x*y) dy) dx,
(8d) SS(x*y) = sin( Integral Integral CC(x*y) dx dy ),
(8e) CC(x*y) = cos( Integral Integral CC(x*y) dx dy ).
DERIVATIVES.
(9a) d/dx Sx = Cx*Dy + Cy*Dx.
(9b) d/dx Cx = -Sx*Dy - Sy*Dx.
(9c) d/dx Dx = -Sx*Cy + Sy*Cx.
(9d) d/dy Sy = Sy*Dx + Sx*Dy.
(9e) d/dy Cy = -Sy*Dx - Sx*Dy.
(9f) d/dy Dy = -Sy*Cx + Sx*Cy.
EXAMPLE
E.g.f.: S(x,y) = x + (-x^3/3! - x*y^2/2! ) + ( x^5/5! - 3*x^3*y^2/(3!*2!) + x*y^4/4! ) + (-x^7/7! + 15*x^5*y^2/(5!*2!) + 15*x^3*y^4/(3!*4!) - x*y^6/6! ) + ( x^9/9! - 35*x^7*y^2/(7!*2!) + 145*x^5*y^4/(5!*4!) - 35*x^3*y^6/(3!*6!) + x*y^8/8! ) + (-x^11/11! + 63*x^9*y^2/(9!*2!) - 1505*x^7*y^4/(7!*4!) - 1505*x^5*y^6/(5!*6!) + 63*x^3*y^8/(3!*8!) - x*y^10/10! ) + ( x^13/13! - 99*x^11*y^2/(11!*2!) + 5985*x^9*y^4/(9!*4!) - 30387*x^7*y^6/(7!*6!) + 5985*x^5*y^8/(5!*8!) - 99*x^3*y^10/(3!*10!) + x*y^12/12! ) + (-x^15/15! + 143*x^13*y^2/(13!*2!) - 16401*x^11*y^4/(11!*4!) + 539679*x^9*y^6/(9!*6!) + 539679*x^7*y^8/(7!*8!) - 16401*x^5*y^10/(5!*10!) + 143*x^3*y^12/(3!*12!) - x*y^14/14! ) + ( x^17/17! - 195*x^15*y^2/(15!*2!) + 36465*x^13*y^4/(13!*4!) - 3275811*x^11*y^6/(11!*6!) + 18679617*x^9*y^8/(9!*8!) - 3275811*x^7*y^10/(7!*10!) + 36465*x^5*y^12/(5!*12!) - 195*x^3*y^14/(3!*14!) + x*y^16/16! ) + (-x^19/19! + 255*x^17*y^2/(17!*2!) - 70785*x^15*y^4/(15!*4!) + 12723711*x^13*y^6/(13!*6!) - 506849409*x^11*y^8/(11!*8!) - 506849409*x^9*y^10/(9!*10!) + 12723711*x^7*y^12/(7!*12!) - 70785*x^5*y^14/(5!*14!) + 255*x^3*y^16/(3!*16!) - x*y^18/18! ) + ( x^21/21! - 323*x^19*y^2/(19!*2!) + 124865*x^17*y^4/(17!*4!) - 38067315*x^15*y^6/(15!*6!) + 4363117473*x^13*y^8/(13!*8!) - 26803260803*x^11*y^10/(11!*10!) + 4363117473*x^9*y^12/(9!*12!) - 38067315*x^7*y^14/(7!*14!) + 124865*x^5*y^16/(5!*16!) - 323*x^3*y^18/(3!*18!) + x*y^20/20! ) + ...
This triangle of coefficients T(n,k) of x^(2*n-2*k+1)*y^(2*k)/((2*n-2*k+1)!*(2*k)!) in e.g.f. S(x,y) begins
1;
-1, -1;
1, -3, 1;
-1, 15, 15, -1;
1, -35, 145, -35, 1;
-1, 63, -1505, -1505, 63, -1;
1, -99, 5985, -30387, 5985, -99, 1;
-1, 143, -16401, 539679, 539679, -16401, 143, -1;
1, -195, 36465, -3275811, 18679617, -3275811, 36465, -195, 1;
-1, 255, -70785, 12723711, -506849409, -506849409, 12723711, -70785, 255, -1;
1, -323, 124865, -38067315, 4363117473, -26803260803, 4363117473, -38067315, 124865, -323, 1;
-1, 399, -205105, 95686591, -22813329825, 1031421316783, 1031421316783, -22813329825, 95686591, -205105, 399, -1;
1, -483, 318801, -212188067, 88405315713, -11952302851203, 77353020714385, -11952302851203, 88405315713, -212188067, 318801, -483, 1; ...
RELATED SERIES.
The e.g.f. of A326801 begins
C(x,y) = sqrt(1/2) * (1 + (-x^2/2! - x*y ) + ( x^4/4! + x*y^3/3! ) + (-x^6/6! + 8*x^4*y^2/(4!*2!) + 8*x^3*y^3/(3!*3!) - x*y^5/5! ) + ( x^8/8! - 24*x^6*y^2/(6!*2!) - 24*x^3*y^5/(3!*5!) + x*y^7/7! ) + (-x^10/10! + 48*x^8*y^2/(8!*2!) - 576*x^6*y^4/(6!*4!) - 576*x^5*y^5/(5!*5!) + 48*x^3*y^7/(3!*7!) - x*y^9/9! ) + ( x^12/12! - 80*x^10*y^2/(10!*2!) + 3200*x^8*y^4/(8!*4!) + 3200*x^5*y^7/(5!*7!) - 80*x^3*y^9/(3!*9!) + x*y^11/11! ) + (-x^14/14! + 120*x^12*y^2/(12!*2!) - 10240*x^10*y^4/(10!*4!) + 160768*x^8*y^6/(8!*6!) + 160768*x^7*y^7/(7!*7!) - 10240*x^5*y^9/(5!*9!) + 120*x^3*y^11/(3!*11!) - x*y^13/13! ) + ...).
The e.g.f. of A326802 begins
D(x,y) = sqrt(1/2) * (1 + (-x^2/2! + x*y ) + ( x^4/4! - x*y^3/3! ) + (-x^6/6! + 8*x^4*y^2/(4!*2!) - 8*x^3*y^3/(3!*3!) + x*y^5/5! ) + ( x^8/8! - 24*x^6*y^2/(6!*2!) + 24*x^3*y^5/(3!*5!) - x*y^7/7! ) + (-x^10/10! + 48*x^8*y^2/(8!*2!) - 576*x^6*y^4/(6!*4!) + 576*x^5*y^5/(5!*5!) - 48*x^3*y^7/(3!*7!) + x*y^9/9! ) + ( x^12/12! - 80*x^10*y^2/(10!*2!) + 3200*x^8*y^4/(8!*4!) - 3200*x^5*y^7/(5!*7!) + 80*x^3*y^9/(3!*9!) - x*y^11/11! ) + (-x^14/14! + 120*x^12*y^2/(12!*2!) - 10240*x^10*y^4/(10!*4!) + 160768*x^8*y^6/(8!*6!) - 160768*x^7*y^7/(7!*7!) + 10240*x^5*y^9/(5!*9!) - 120*x^3*y^11/(3!*11!) + x*y^13/13! ) + ...).
The e.g.f. of A326552 begins
SS(x*y) = (x*y) - 8*(x*y)^3/3!^2 + 576*(x*y)^5/5!^2 - 160768*(x*y)^7/7!^2 + 123535360*(x*y)^9/9!^2 - 212713734144*(x*y)^11/11!^2 + 716196297048064*(x*y)^13/13!^2 - 4280584942657732608*(x*y)^15/15!^2 + 42250703121584165486592*(x*y)^17/17!^2 - 651154631135458759089848320*(x*y)^19/19!^2 + 14983590319172065236171175755776*(x*y)^21/21!^2 + ... + A326552(n)*(x*y)^(2*n-1)/(2*n-1)! + ...
such that
SS(x*y) = Dx*Dy - Cx*Cy - Sx*Sy.
The e.g.f. of A326551 begins
CC(x*y) = 1 - 2*(x*y)^2/2!^2 + 56*(x*y)^4/4!^2 - 8336*(x*y)^6/6!^2 + 3985792*(x*y)^8/8!^2 - 4679517952*(x*y)^10/10!^2 + 11427218287616*(x*y)^12/12!^2 - 51793067942397952*(x*y)^14/14!^2 + 400951893341645930496*(x*y)^16/16!^2 - 4975999084909976839454720*(x*y)^18/18!^2 + 94178912073481319162642169856*(x*y)^20/20!^2 -+ ... + A326551(n)*(x*y)^(2*n)/(2*n)! + ...
such that
CC(x*y)^2 = (Cx*Dy + Cy*Dx)^2 + (Sx*Dy + Sy*Dx)^2 + (Sx*Cy - Sy*Cx)^2,
and CC(x*y)^2 + SS(x*y)^2 = 1.
PROG
(PARI)
{TSx(n, k) = my(Cx=1, Sx=x, Dx=1, Cy=1, Sy=y, Dy=1);
for(i=0, 2*n+1,
Sx = intformal( Cx*Dy + Cy*Dx, x) + O(x^(2*n+2));
Cx = sqrt(1/2) - intformal( Sx*Dy + Sy*Dx, x);
Dx = sqrt(1/2) - intformal( Sx*Cy - Sy*Cx, x);
Sy = intformal( Cy*Dx + Cx*Dy, y) + O(y^(2*n+2));
Cy = sqrt(1/2) - intformal( Sy*Dx + Sx*Dy, y);
Dy = sqrt(1/2) - intformal( Sy*Cx - Sx*Cy, y);
);
round( (2*n-2*k+1)!*(2*k)! * polcoeff( polcoeff(Sx, 2*n-2*k+1, x), 2*k, y) )}
for(n=0, 10, for(k=0, n, print1( TSx(n, k), ", ")); print(""))
CROSSREFS
Cf. A326801 (Cx), A326802 (Dx), A326803 (central terms).
Cf. A326551 (CC), A326552 (SS), A326797.
KEYWORD
sign,tabl
AUTHOR
Paul D. Hanna, Jul 27 2019
STATUS
approved
A326802 Consider the e.g.f. D(x,y) = sqrt(1/2) * Sum_{n>=0} Sum_{k=0..2*n} T(n,k) * x^(2*n-k) * y^k / ((2*n-k)!*k!) and related functions S(x,y) and C(x,y), as defined in the Formula section. Sequence gives the triangular array of coefficients T(n,k) (n>=0, 0<=k<=2*n) of D(x,y). +10
6
1, -1, 1, 0, 1, 0, 0, -1, 0, -1, 0, 8, -8, 0, 1, 0, 1, 0, -24, 0, 0, 24, 0, -1, 0, -1, 0, 48, 0, -576, 576, 0, -48, 0, 1, 0, 1, 0, -80, 0, 3200, 0, 0, -3200, 0, 80, 0, -1, 0, -1, 0, 120, 0, -10240, 0, 160768, -160768, 0, 10240, 0, -120, 0, 1, 0, 1, 0, -168, 0, 24960, 0, -1433600, 0, 0, 1433600, 0, -24960, 0, 168, 0, -1, 0, -1, 0, 224, 0, -51520, 0, 6723584, 0, -123535360, 123535360, 0, -6723584, 0, 51520, 0, -224, 0, 1, 0, 1, 0, -288, 0, 94976, 0, -22586368, 0, 1615675392, 0, 0, -1615675392, 0, 22586368, 0, -94976, 0, 288, 0, -1, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,12
LINKS
Paul D. Hanna, Table of n, a(n) for n = 0..3720 (the first 60 rows of the triangle).
FORMULA
The e.g.f. Dx = D(x,y) and related functions Sx = S(x,y), Cx = C(x,y), Sy = S(y,x), Cy = C(y,x), and Dy = D(y,x) satisfy the following relations.
DEFINITION.
(1a) Sx = Integral Cx*Dy + Cy*Dx dx,
(1b) Cx = sqrt(1/2) - Integral Sx*Dy + Sy*Dx dx,
(1c) Dx = sqrt(1/2) - Integral Sx*Cy - Sy*Cx dx,
(2a) Sy = Integral Cy*Dx + Cx*Dy dy,
(2b) Cy = sqrt(1/2) - Integral Sy*Dx + Sx*Dy dy,
(2c) Dy = sqrt(1/2) - Integral Sy*Cx - Sx*Cy dy.
IDENTITIES.
(3a) Dx^2 + Cx^2 + Sx^2 = 1.
(3b) Dy^2 + Cy^2 + Sy^2 = 1.
(4a) Dx*(d/dx Dx) + Cx*(d/dx Cx) + Sx*(d/dx Sx) = 0.
(4b) Dy*(d/dy Dy) + Cy*(d/dy Cy) + Sy*(d/dy Sy) = 0.
(4c) Dy*(d/dx Dx) - Cy*(d/dx Cx) - Sy*(d/dx Sx) = 0.
(4d) Dx*(d/dy Dy) - Cx*(d/dy Cy) - Sx*(d/dy Sy) = 0.
(5a) (Dx*Dy - Cx*Cy - Sx*Sy)^2 + (d/dx Dx)^2 + (d/dx Cx)^2 + (d/dx Sx)^2 = 1.
(5b) (Dx*Dy - Cx*Cy - Sx*Sy)^2 + (d/dy Dy)^2 + (d/dy Cy)^2 + (d/dy Sy)^2 = 1.
RELATED FUNCTIONS.
(6a) SS(x*y) = Dx*Dy - Cx*Cy - Sx*Sy.
(6b) d/dx SS(x*y) = Dx*(d/dx Dy) - Cx*(d/dx Cy) - Sx*(d/dx Sy).
(6c) d/dy SS(x*y) = Dy*(d/dy Dx) - Cy*(d/dy Cx) - Sy*(d/dy Sx).
(7a) CC(x*y)^2 = (Cx*Dy + Cy*Dx)^2 + (Sx*Dy + Sy*Dx)^2 + (Sx*Cy - Sy*Cx)^2.
(7b) CC(x*y)^2 = (d/dx Dx)^2 + (d/dx Cx)^2 + (d/dx Sx)^2.
(7c) CC(x*y)^2 = (d/dy Dy)^2 + (d/dy Cy)^2 + (d/dy Sy)^2.
In the above, CC(x) and SS(x) are the e.g.f.s of A326551 and A326552 defined by
(8a) CC(x*y)^2 + SS(x*y)^2 = 1,
(8b) SS(x*y) = Integral CC(x*y) * (Integral CC(x*y) dy) dx,
(8c) CC(x*y) = 1 - Integral SS(x*y) * (Integral CC(x*y) dy) dx,
(8d) SS(x*y) = sin( Integral Integral CC(x*y) dx dy ),
(8e) CC(x*y) = cos( Integral Integral CC(x*y) dx dy ).
DERIVATIVES.
(9a) d/dx Sx = Cx*Dy + Cy*Dx.
(9b) d/dx Cx = -Sx*Dy - Sy*Dx.
(9c) d/dx Dx = -Sx*Cy + Sy*Cx.
(9d) d/dy Sy = Sy*Dx + Sx*Dy.
(9e) d/dy Cy = -Sy*Dx - Sx*Dy.
(9f) d/dy Dy = -Sy*Cx + Sx*Cy.
EXAMPLE
E.g.f.: D(x,y) = sqrt(1/2) * (1 + (-x^2/2! + x*y ) + ( x^4/4! - x*y^3/3! ) + (-x^6/6! + 8*x^4*y^2/(4!*2!) - 8*x^3*y^3/(3!*3!) + x*y^5/5! ) + ( x^8/8! - 24*x^6*y^2/(6!*2!) + 24*x^3*y^5/(3!*5!) - x*y^7/7! ) + (-x^10/10! + 48*x^8*y^2/(8!*2!) - 576*x^6*y^4/(6!*4!) + 576*x^5*y^5/(5!*5!) - 48*x^3*y^7/(3!*7!) + x*y^9/9! ) + ( x^12/12! - 80*x^10*y^2/(10!*2!) + 3200*x^8*y^4/(8!*4!) - 3200*x^5*y^7/(5!*7!) + 80*x^3*y^9/(3!*9!) - x*y^11/11! ) + (-x^14/14! + 120*x^12*y^2/(12!*2!) - 10240*x^10*y^4/(10!*4!) + 160768*x^8*y^6/(8!*6!) - 160768*x^7*y^7/(7!*7!) + 10240*x^5*y^9/(5!*9!) - 120*x^3*y^11/(3!*11!) + x*y^13/13! ) + ( x^16/16! - 168*x^14*y^2/(14!*2!) + 24960*x^12*y^4/(12!*4!) - 1433600*x^10*y^6/(10!*6!) + 1433600*x^7*y^9/(7!*9!) - 24960*x^5*y^11/(5!*11!) + 168*x^3*y^13/(3!*13!) - x*y^15/15! ) + (-1*x^18/18! + 224*x^16*y^2/(16!*2!) - 51520*x^14*y^4/(14!*4!) + 6723584*x^12*y^6/(12!*6!) - 123535360*x^10*y^8/(10!*8!) + 123535360*x^9*y^9/(9!*9!) - 6723584*x^7*y^11/(7!*11!) + 51520*x^5*y^13/(5!*13!) - 224*x^3*y^15/(3!*15!) + x*y^17/17! ) + ( x^20/20! - 288*x^18*y^2/(18!*2!) + 94976*x^16*y^4/(16!*4!) - 22586368*x^14*y^6/(14!*6!) + 1615675392*x^12*y^8/(12!*8!) - 1615675392*x^9*y^11/(9!*11!) + 22586368*x^7*y^13/(7!*13!) - 94976*x^5*y^15/(5!*15!) + 288*x^3*y^17/(3!*17!) - x*y^19/19! ) + ...).
This triangle of coefficients T(n,k) of x^(2*n-k)*y^k/((2*n-k)!*k!) in sqrt(2)*D(x,y) begins
1;
-1, 1, 0;
1, 0, 0, -1, 0;
-1, 0, 8, -8, 0, 1, 0;
1, 0, -24, 0, 0, 24, 0, -1, 0;
-1, 0, 48, 0, -576, 576, 0, -48, 0, 1, 0;
1, 0, -80, 0, 3200, 0, 0, -3200, 0, 80, 0, -1, 0;
-1, 0, 120, 0, -10240, 0, 160768, -160768, 0, 10240, 0, -120, 0, 1, 0;
1, 0, -168, 0, 24960, 0, -1433600, 0, 0, 1433600, 0, -24960, 0, 168, 0, -1, 0;
-1, 0, 224, 0, -51520, 0, 6723584, 0, -123535360, 123535360, 0, -6723584, 0, 51520, 0, -224, 0, 1, 0;
1, 0, -288, 0, 94976, 0, -22586368, 0, 1615675392, 0, 0, -1615675392, 0, 22586368, 0, -94976, 0, 288, 0, -1, 0;
-1, 0, 360, 0, -161280, 0, 61458432, 0, -10447847424, 0, 212713734144, -212713734144, 0, 10447847424, 0, -61458432, 0, 161280, 0, -360, 0, 1, 0;
1, 0, -440, 0, 257280, 0, -144420864, 0, 46282211328, 0, -3835832827904, 0, 0, 3835832827904, 0, -46282211328, 0, 144420864, 0, -257280, 0, 440, 0, -1, 0; ...
CENTRAL TERMS.
The central terms are found in 1 + SS(x*y) = 1 + Dx*Dy - Cx*Cy - Sx*Sy:
[1, 1, 0, -8, 0, 576, 0, -160768, 0, 123535360, 0, -212713734144, 0, 716196297048064, 0, -4280584942657732608, ...] (cf. A326552).
RELATED SERIES.
The e.g.f. of A326800 begins
S(x,y) = x + (-x^3/3! - x*y^2/2! ) + ( x^5/5! - 3*x^3*y^2/(3!*2!) + x*y^4/4! ) + (-x^7/7! + 15*x^5*y^2/(5!*2!) + 15*x^3*y^4/(3!*4!) - x*y^6/6! ) + ( x^9/9! - 35*x^7*y^2/(7!*2!) + 145*x^5*y^4/(5!*4!) - 35*x^3*y^6/(3!*6!) + x*y^8/8! ) + (-x^11/11! + 63*x^9*y^2/(9!*2!) - 1505*x^7*y^4/(7!*4!) - 1505*x^5*y^6/(5!*6!) + 63*x^3*y^8/(3!*8!) - x*y^10/10! ) + ( x^13/13! - 99*x^11*y^2/(11!*2!) + 5985*x^9*y^4/(9!*4!) - 30387*x^7*y^6/(7!*6!) + 5985*x^5*y^8/(5!*8!) - 99*x^3*y^10/(3!*10!) + x*y^12/12! ) + (-x^15/15! + 143*x^13*y^2/(13!*2!) - 16401*x^11*y^4/(11!*4!) + 539679*x^9*y^6/(9!*6!) + 539679*x^7*y^8/(7!*8!) - 16401*x^5*y^10/(5!*10!) + 143*x^3*y^12/(3!*12!) - x*y^14/14! ) + ...
The e.g.f. of A326801 begins
C(x,y) = sqrt(1/2) * (1 + (-x^2/2! - x*y ) + ( x^4/4! + x*y^3/3! ) + (-x^6/6! + 8*x^4*y^2/(4!*2!) + 8*x^3*y^3/(3!*3!) - x*y^5/5! ) + ( x^8/8! - 24*x^6*y^2/(6!*2!) - 24*x^3*y^5/(3!*5!) + x*y^7/7! ) + (-x^10/10! + 48*x^8*y^2/(8!*2!) - 576*x^6*y^4/(6!*4!) - 576*x^5*y^5/(5!*5!) + 48*x^3*y^7/(3!*7!) - x*y^9/9! ) + ( x^12/12! - 80*x^10*y^2/(10!*2!) + 3200*x^8*y^4/(8!*4!) + 3200*x^5*y^7/(5!*7!) - 80*x^3*y^9/(3!*9!) + x*y^11/11! ) + (-x^14/14! + 120*x^12*y^2/(12!*2!) - 10240*x^10*y^4/(10!*4!) + 160768*x^8*y^6/(8!*6!) + 160768*x^7*y^7/(7!*7!) - 10240*x^5*y^9/(5!*9!) + 120*x^3*y^11/(3!*11!) - x*y^13/13! ) + ...).
The e.g.f. of A326552 begins
SS(x*y) = (x*y) - 8*(x*y)^3/3!^2 + 576*(x*y)^5/5!^2 - 160768*(x*y)^7/7!^2 + 123535360*(x*y)^9/9!^2 - 212713734144*(x*y)^11/11!^2 + 716196297048064*(x*y)^13/13!^2 - 4280584942657732608*(x*y)^15/15!^2 + 42250703121584165486592*(x*y)^17/17!^2 - 651154631135458759089848320*(x*y)^19/19!^2 + 14983590319172065236171175755776*(x*y)^21/21!^2 + ... + A326552(n)*(x*y)^(2*n-1)/(2*n-1)! + ...
such that
SS(x*y) = Dx*Dy - Cx*Cy - Sx*Sy.
The e.g.f. of A326551 begins
CC(x*y) = 1 - 2*(x*y)^2/2!^2 + 56*(x*y)^4/4!^2 - 8336*(x*y)^6/6!^2 + 3985792*(x*y)^8/8!^2 - 4679517952*(x*y)^10/10!^2 + 11427218287616*(x*y)^12/12!^2 - 51793067942397952*(x*y)^14/14!^2 + 400951893341645930496*(x*y)^16/16!^2 - 4975999084909976839454720*(x*y)^18/18!^2 + 94178912073481319162642169856*(x*y)^20/20!^2 -+ ... + A326551(n)*(x*y)^(2*n)/(2*n)! + ...
such that
CC(x*y)^2 = (Cx*Dy + Cy*Dx)^2 + (Sx*Dy + Sy*Dx)^2 + (Sx*Cy - Sy*Cx)^2,
and CC(x*Y)^2 + SS(x*y)^2 = 1.
PROG
(PARI)
{TDx(n, k) = my(Cx=1, Sx=x, Dx=1, Cy=1, Sy=y, Dy=1);
for(i=0, 2*n+1,
Sx = intformal( Cx*Dy + Cy*Dx, x) + O(x^(2*n+2));
Cx = sqrt(1/2) - intformal( Sx*Dy + Sy*Dx, x);
Dx = sqrt(1/2) - intformal( Sx*Cy - Sy*Cx, x);
Sy = intformal( Cy*Dx + Cx*Dy, y) + O(y^(2*n+2));
Cy = sqrt(1/2) - intformal( Sy*Dx + Sx*Dy, y);
Dy = sqrt(1/2) - intformal( Sy*Cx - Sx*Cy, y);
);
round( (2*n-k)!*k! * polcoeff( polcoeff(sqrt(2)*Dx, 2*n-k, x), k, y) )}
for(n=0, 10, for(k=0, 2*n, print1( TDx(n, k), ", ")); print(""))
CROSSREFS
Cf. A326800 (Sx), A326801 (Cx), A326551 (CC), A326552 (SS).
KEYWORD
sign,tabf
AUTHOR
Paul D. Hanna, Jul 27 2019
STATUS
approved
A326556 E.g.f. C(x)^2 = Sum_{n>=0} a(n)*x^(2*n)/(2*n)!^2, where C(x) = cos( Integral 1/x * (Integral C(x) dx) dx ) is the e.g.f of A326551. +10
1
1, -4, 256, -67072, 49479680, -82817122304, 273099601739776, -1606512897507196928, 15659025634284911198208, -238894370882781809622384640, 5451274531297360096585324691456, -179296966081016547805899589056200704, 8242844472527700570663352676068232265728, -516102091343047279882754030489835708929277952, 43042816831864259208854418353099287467922680709120 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
COMMENTS
The e.g.f. C(x)^2 can be derived from the functions described by A326800, A326801, and A326802.
LINKS
EXAMPLE
E.g.f.: C(x)^2 = 1 - 4*x^2/2!^2 + 256*x^4/4!^2 - 67072*x^6/6!^2 + 49479680*x^8/8!^2 - 82817122304*x^10/10!^2 + 273099601739776*x^12/12!^2 - 1606512897507196928*x^14/14!^2 + 15659025634284911198208*x^16/16!^2 - 238894370882781809622384640*x^18/18!^2 + 5451274531297360096585324691456*x^20/20!^2 + ...
where C(x) is the e.g.f. of A326551:
C(x) = 1 - 2*x^2/2!^2 + 56*x^4/4!^2 - 8336*x^6/6!^2 + 3985792*x^8/8!^2 - 4679517952*x^10/10!^2 + 11427218287616*x^12/12!^2 - 51793067942397952*x^14/14!^2 + 400951893341645930496*x^16/16!^2 - 4975999084909976839454720*x^18/18!^2 + 94178912073481319162642169856*x^20/20!^2 -+ ...
such that C(x) = cos( Integral 1/x * (Integral C(x) dx) dx ),
note also C(x*y) = cos( Integral Integral C(x*y) dx dy ).
PROG
(PARI)
{a(n) = my(C=1, S=x); for(i=1, 2*n,
S = intformal( C/x * intformal( C +x*O(x^(2*n)) ) );
C = 1 - intformal( S/x * intformal( C +x*O(x^(2*n)) ) ); ); (2*n)!^2*polcoeff(C^2, 2*n)}
for(n=0, 30, print1(a(n), ", "))
CROSSREFS
KEYWORD
sign
AUTHOR
Paul D. Hanna, Jul 28 2019
STATUS
approved
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Last modified August 31 00:13 EDT 2024. Contains 375550 sequences. (Running on oeis4.)