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Decimal expansion of Pi*log(2).
+10
9
2, 1, 7, 7, 5, 8, 6, 0, 9, 0, 3, 0, 3, 6, 0, 2, 1, 3, 0, 5, 0, 0, 6, 8, 8, 8, 9, 8, 2, 3, 7, 6, 1, 3, 9, 4, 7, 3, 3, 8, 5, 8, 3, 7, 0, 0, 3, 6, 9, 2, 8, 6, 2, 9, 4, 3, 2, 5, 7, 9, 5, 2, 5, 3, 1, 9, 4, 3, 0, 8, 5, 4, 9, 1, 7, 6, 7, 4, 1, 9, 8, 6, 4, 3, 0, 3, 2, 8, 9, 6, 1, 6, 1, 0, 6, 6, 3, 0, 2, 5, 0, 5, 7, 6, 1
OFFSET
1,1
COMMENTS
Madelung constant b2(2), negated.
REFERENCES
G. Boros and V. H. Moll, Irresistible Integrals: Symbolics, Analysis and Experiments in the Evaluation of Integrals, Cambridge University Press, 2004 (equation 13.6.6).
LINKS
Eric Weisstein's World of Mathematics, Madelung Constants
FORMULA
Pi*log(2) = -(8/3)*int(log(x)/sqrt(1+4*x-4*x^2), x=0..1). - John M. Campbell, Feb 07 2012
Pi*log(2) = int((x/sin(x))^2, x=0..Pi/2) = int(log(x^2+1)/(x^2+1), x=0..infinity) = int(-log(cos(x)), x=-Pi/2..Pi/2) = int(arctan(1/x)^2, x=0..infinity). - Jean-François Alcover, May 30 2013
From Amiram Eldar, Jul 11 2020: (Start)
Equals Integral_{x=-1..1} arcsin(x) dx / x.
Equals Integral_{x=-Pi/2..Pi/2} x*cot(x) dx. (End)
Equals Integral_{x = 0..oo} log(x^2 + 4)/(x^2 + 4) dx. - Peter Bala, Jul 22 2022
Equals -Im(Polylog(2, 2)). - Mohammed Yaseen, Jul 03 2024
EXAMPLE
2.1775860903036021305006888982376139...
MATHEMATICA
RealDigits[Pi Log[2], 10, 120][[1]] (* Harvey P. Dale, Dec 31 2011 *)
CROSSREFS
Cf. A000796 (Pi), A002162 (log(2)), A173623.
KEYWORD
nonn,cons,easy
AUTHOR
Eric W. Weisstein, Jul 07 2003
EXTENSIONS
Corrected by Antti Ahti (antti.ahti(AT)tkk.fi), Nov 17 2004
More terms from Benoit Cloitre, May 21 2005
STATUS
approved
Decimal expansion of Pi/8*(6*zeta(3)+Pi^2*log(2)+4*log(2)^3).
+10
4
6, 0, 4, 1, 8, 8, 2, 9, 0, 9, 7, 7, 5, 0, 9, 3, 5, 2, 2, 1, 5, 0, 4, 2, 4, 1, 3, 0, 6, 7, 5, 9, 9, 5, 9, 8, 5, 5, 0, 8, 7, 1, 0, 3, 0, 5, 7, 7, 4, 6, 4, 1, 9, 0, 7, 2, 5, 8, 6, 0, 1, 0, 1, 5, 2, 6, 0, 0, 4, 3, 0, 2, 5, 4, 6, 5, 5, 7, 5, 8, 1, 6, 0, 4, 0, 4, 7, 0, 8, 2, 6, 5, 8, 8, 2, 6, 1, 6, 9, 5, 1, 5, 5, 8, 1
OFFSET
1,1
COMMENTS
The absolute value of the integral {x=0..Pi/2} log(sin(x))^3 dx. The absolute value of m=3 of sqrt(Pi)/2*(d^m/da^m(gamma((a+1)/2)/gamma(a/2+1))) at a=0. - Seiichi Kirikami and Peter J. C. Moses, Oct 07 2011
REFERENCES
I. S. Gradshteyn and I. M. Ryzhik, Table of Integrals, Series and Products, 4th edition, 3.621.1
LINKS
K. S. Kolbig, On the integral int_0^Pi/2 log^n cos x log^p sin x dx, Math. Comp. 40 (162) (1983) 565-570, r_{3,0}
FORMULA
Equals A019675*(6*A002117 + A002388*A002162 + 4*A002162^3).
EXAMPLE
6.041882909775093522150424130675995...
MAPLE
Pi/8*(6*Zeta(3)+Pi^2*log(2)+4*log(2)^3) ; evalf(%) ; # R. J. Mathar, Oct 08 2011
MATHEMATICA
RealDigits[N[Pi/8 (6 Zeta[3] + Pi^2 Log[2] + 4 Log[2]^3), 150][[1]]
Sqrt[Pi]/2*Derivative[3][Gamma[(#+1)/2]/Gamma[#/2+1]&][0] // RealDigits[#, 10, 105]& // First (* Jean-François Alcover, Mar 25 2013 *)
PROG
(PARI) Pi/8*(6*zeta(3)+Pi^2*log(2)+4*log(2)^3) \\ G. C. Greubel, Feb 12 2017
CROSSREFS
KEYWORD
cons,nonn
AUTHOR
Seiichi Kirikami, Oct 07 2011
STATUS
approved
Decimal expansion of Pi^3*log(2)/24 - 3*Pi*zeta(3)/16.
+10
3
1, 8, 7, 4, 2, 6, 4, 2, 2, 8, 2, 8, 2, 3, 1, 0, 8, 0, 2, 6, 4, 5, 6, 9, 3, 1, 2, 2, 7, 3, 2, 7, 5, 0, 8, 1, 2, 5, 3, 0, 6, 9, 0, 1, 1, 7, 7, 0, 3, 1, 1, 5, 5, 7, 0, 8, 1, 0, 3, 2, 6, 0, 8, 3, 8, 8, 1, 8, 0, 2, 3, 3, 3, 1, 0, 6, 2, 0, 2, 8, 4, 9, 7, 6, 4, 9, 9, 2, 3, 1, 0, 6, 0, 2, 4, 4, 5, 8, 8, 1
OFFSET
0,2
COMMENTS
The absolute value of the integral {x=0..Pi/2} x^2*log(sin(x )) dx or (d^2/da^2 (integral {x=0..Pi/2} cos(ax)*log(sin(x )) dx)) at a=0. The absolute value of (sum {n=1..infinity} (limit { a -> 0} (d^2/da^2 (sin((a+2n)*Pi/2)/n/(a+2n)))))-(Pi/2)^3*log(2)/3. [Seiichi Kirikami and Peter J. C. Moses]
REFERENCES
I. S. Gradshteyn and I. M. Ryzhik, Table of Integrals, series and Products, 1.441.2, 4th edition, log(sin(x))=-(sum {1..infinity} cos(2nx)/n)-log(2).
LINKS
R. E. Crandall, J. P. Buhler, On the evaluation of Euler sums, Exper. Math. 3 (4) (1994) 275 (discuss int_{0..1} x^n*cot(x) dx which is obtained by partial integration).
S. Koyama and N. Kurokawa, Euler’s integrals and multiple sine functions, Proc. Amer. Math. Soc. 133(2005), 1257-1265.
FORMULA
Equals A091925*A002162/24-3*A000796*A002117/16.
EXAMPLE
0.18742642282823108026...
MATHEMATICA
RealDigits[ N[Pi (2 Pi^2 Log[2] - 9 Zeta[3]) / 48, 105] ][[1]]
PROG
(PARI) Pi^3*log(2)/24 - 3*Pi*zeta(3)/16 \\ Michel Marcus, Oct 25 2017
CROSSREFS
KEYWORD
cons,nonn
AUTHOR
Seiichi Kirikami, Aug 03 2011
STATUS
approved
Decimal expansion of Pi^4*log(2)/64 - 9*Pi^2*zeta(3)/64 + 93*zeta(5)/128.
+10
3
1, 4, 0, 0, 2, 4, 1, 0, 1, 7, 0, 6, 8, 5, 2, 3, 1, 7, 1, 0, 0, 2, 7, 0, 5, 7, 8, 8, 7, 5, 5, 3, 5, 0, 7, 5, 3, 2, 2, 4, 2, 8, 2, 1, 2, 7, 8, 5, 7, 7, 0, 5, 0, 8, 9, 8, 8, 1, 8, 5, 9, 6, 3, 1, 4, 1, 1, 6, 2, 7, 7, 1, 4, 6, 3, 7, 0, 5, 9, 7, 0, 2, 3, 0, 4, 9, 0, 7, 6, 1, 1, 0, 2, 6, 6, 3, 0, 9, 0, 5
OFFSET
0,2
COMMENTS
The absolute value of the integral {x=0..Pi/2} x^3*log(sin(x )) dx or (d^3/da^3 (integral {x=0..Pi/2} sin(ax )*log(sin(x )) dx)) at a=0. The absolute value of (sum {n=1..infinity} (limit { a -> 0} (d^3/da^3 ((1-cos((a+2n)*Pi/2))/n/(a+2n)))))-(Pi/2)^4*log(2)/4. [Seiichi Kirikami and Peter J. C. Moses]
REFERENCES
I. S. Gradshteyn and I. M. Ryzhik, Table of Integrals, series and Products, 4th edition, 1.441.2, log(sin(x))=-(sum {1..infinity} cos(2nx)/n)-log(2).
LINKS
S. Koyama and N. Kurokawa, Euler’s integrals and multiple sine functions, Proc. Amer. Math. Soc. 133(2005), 1257-1265.
FORMULA
Equals A092425*A002162/64-9*A002388*A002117/64+93*A013663/128.
EXAMPLE
-0.14002410170685231710...
MATHEMATICA
RealDigits[N[(2 Pi^4 Log[2] - 18 Pi^2 Zeta[3] + 93 Zeta[5]) / 128, 105]][[1]]
PROG
(PARI) Pi^4*log(2)/64 - 9*Pi^2*zeta(3)/64 + 93*zeta(5)/128 \\ Michel Marcus, Oct 25 2017
CROSSREFS
KEYWORD
cons,nonn
AUTHOR
Seiichi Kirikami, Aug 03 2011
STATUS
approved
Decimal expansion of Pi/2*(Pi^2/12 + (log(2))^2).
+10
3
2, 0, 4, 6, 6, 2, 2, 0, 2, 4, 4, 7, 2, 7, 4, 0, 6, 4, 6, 1, 6, 9, 6, 4, 1, 0, 0, 8, 1, 7, 6, 9, 7, 3, 4, 7, 6, 6, 3, 7, 4, 4, 1, 9, 5, 3, 4, 9, 4, 6, 5, 6, 2, 6, 0, 6, 1, 0, 2, 6, 8, 5, 5, 2, 7, 2, 5, 9, 0, 6, 6, 8, 7, 9, 5, 1, 2, 1, 7, 3, 3, 6, 5, 8, 4, 6, 8, 8, 4, 6, 7, 6, 3, 2, 9, 1, 2, 5, 2, 5, 3, 4, 3, 4, 7
OFFSET
1,1
COMMENTS
The value of the integral_{x=0..Pi/2} log(sin(x))^2 dx. The value of sqrt(Pi)/2*(d^2/da^2(gamma((a+1)/2)/gamma(a/2+1))) at a=0. - Seiichi Kirikami and Peter J. C. Moses, Oct 07 2011
REFERENCES
I. S. Gradshteyn and I. M. Ryzhik, Table of Integrals, Series and Products, 4th edition, 3.621.1
LINKS
K. S. Kolbig, On the integral int_0^Pi/2 log^n cos x log^p sin x dx, Math. Comp. 40 (162) (1983) 565-570, r_{2,0}
FORMULA
Equals A019669*(A072691 + A002162^2).
Equals Integral_{x=0..1} log(x)^2/sqrt(1-x^2) dx. - Amiram Eldar, May 27 2023
EXAMPLE
2.04662202447274064616964100817...
MATHEMATICA
RealDigits[N[Pi/2 (Pi^2/12 + Log[2]^2), 150] [[1]]
PROG
(PARI) Pi/2*(Pi^2/12+(log(2))^2) \\ Michel Marcus, Jan 13 2015
CROSSREFS
KEYWORD
cons,nonn
AUTHOR
Seiichi Kirikami, Oct 07 2011
STATUS
approved
Decimal expansion of (-2*Catalan + Pi*log(2))/2.
+10
2
1, 7, 2, 8, 2, 7, 4, 5, 0, 9, 7, 4, 5, 8, 2, 0, 5, 0, 1, 9, 5, 7, 4, 0, 9, 3, 4, 1, 8, 6, 4, 2, 2, 8, 6, 2, 8, 9, 5, 1, 4, 2, 4, 7, 5, 9, 0, 2, 9, 7, 1, 0, 1, 2, 8, 9, 6, 3, 9, 9, 5, 0, 6, 9, 7, 5, 3, 9, 1, 2, 5, 4, 8, 1, 2, 1, 1, 6, 2, 2, 3, 7, 3, 5, 8, 0, 7, 9, 6, 7, 8, 7, 9, 2, 1, 6, 4, 0, 6, 2, 8, 0
OFFSET
0,2
LINKS
Su Hu, Min-soo Kim, Euler's integral, multiple cosine function and zeta values, arXiv:2201.011247 (2023), Example 2.5.
Eric Weisstein's World of Mathematics, Radial Integrals
FORMULA
Equals Integral_{x=0..1; y=0..1} [x^2+y^2>1]/(x^2+y^2) where [] is the Iverson bracket.
Equals Integral_{0..1} log(1+x^2)/(1+x^2) dx. - Jean-François Alcover, Sep 22 2014
Equals Sum_{k>=1} (-1)^(k+1) * H(k)/(2*k+1), where H(k) = A001008(k)/A002805(k) is the k-th harmonic number. - Amiram Eldar, Jul 22 2020
EXAMPLE
0.17282745097458205019574...
MAPLE
evalf(-Catalan+Pi*log(2)/2) ; # R. J. Mathar, Apr 01 2010
MATHEMATICA
First[RealDigits[Pi*Log[2]/2 - Catalan, 10, 100]] (* Paolo Xausa, Apr 27 2024 *)
PROG
(PARI) Pi*log(2)/2 - Catalan \\ Michel Marcus, Sep 22 2014
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Eric W. Weisstein, Apr 15 2004
STATUS
approved
Decimal expansion of (2*Pi^5*log(2) - 30*Pi^3*zeta(3) + 225*Pi*zeta(5))/320.
+10
0
1, 2, 2, 0, 4, 7, 2, 9, 5, 8, 8, 5, 9, 2, 8, 7, 2, 1, 6, 3, 3, 2, 6, 0, 2, 9, 6, 2, 8, 2, 2, 9, 5, 2, 8, 8, 1, 4, 4, 5, 6, 8, 7, 2, 0, 5, 0, 5, 6, 9, 2, 4, 2, 8, 1, 5, 5, 4, 3, 8, 5, 7, 9, 2, 6, 4, 2, 7, 6, 2, 1, 5, 6, 7, 7, 7, 9, 5, 5, 8, 6, 5, 2, 1, 0, 9, 1, 3, 5, 3, 0, 9, 5, 5, 0, 4, 5, 5, 8, 2, 8, 0, 9, 3, 5
OFFSET
0,2
COMMENTS
The absolute value of the integral{x=0..Pi/2} x^4*log(sin(x )) dx or(d^4/da^4(integral {x=0..Pi/2} cos(ax)*log(sin(x )) dx)) at a=0. The absolute value of m=2 of (-1)^(m+1)*(sum {n=1..infinity} (limit {a -> 0} (d^(2m)/da^(2m)(sin((a+2n)*Pi/2)/n/(a+2n)))))-(Pi/2)^(2m+1)*log(2)/(2m+1). [Seiichi Kirikami and Peter J. C. Moses, Sep 01 2011]
REFERENCES
I. S. Gradshteyn and I. M. Ryzhik, Table of Integrals, Series and Products, 4th edition, 1.441.2
FORMULA
Equals (2*A092731*A002162-30*A091925*A002117+225*A000796*A013663)/320.
EXAMPLE
0.12204729588592872163...
MATHEMATICA
RealDigits[ N[Pi (2 Pi^4*Log[2]-30 Pi^2*Zeta[3]+225 zeta[5])/320, 150]][[1]]
CROSSREFS
KEYWORD
cons,nonn
AUTHOR
Seiichi Kirikami, Sep 01 2011
STATUS
approved
Decimal expansion of (4*Pi^6*log(2) - 90*Pi^4*zeta(3) + 1350*Pi^2*zeta(5) - 5715*zeta(7))/1536.
+10
0
1, 1, 7, 5, 7, 5, 8, 3, 4, 0, 7, 2, 3, 3, 2, 4, 8, 2, 0, 6, 2, 4, 2, 9, 0, 6, 7, 9, 4, 9, 1, 4, 7, 5, 8, 4, 3, 3, 4, 1, 6, 4, 3, 8, 9, 9, 8, 1, 6, 2, 9, 0, 8, 8, 8, 6, 9, 5, 3, 0, 2, 4, 7, 6, 4, 9, 1, 9, 1, 2, 8, 4, 2, 7, 1, 5, 5, 9, 4, 7, 1, 1, 8, 2, 6, 8, 8, 8, 9, 0, 0, 3, 1, 4, 1, 1, 5, 9, 4, 4, 7, 1, 9, 9, 4
OFFSET
0,3
COMMENTS
The absolute value of the integral {x=0..Pi/2} x^5*log(sin(x )) dx or (d^5/da^5 (integral {x=0..Pi/2} sin(ax)*log(sin(x )) dx)) at a=0. The absolute value of m=2 of (-1)^(m+1)*(sum {n=1..infinity} (limit {a -> 0} (d^(2m+1)/da^(2m+1) ((1-cos((a+2n)*Pi/2))/n/(a+2n)))))-(pi/2)^2(m+1)*log(2)/2/(m+1).
REFERENCES
I. S. Gradshteyn and I. M. Ryzhik, Table of Integrals, Series and Products, 4th edition, 1.441.2
FORMULA
Equals (4*A092732*A002162-90*A092425*A002117+1350*A002388*A013663-5715*A013665)/1536.
EXAMPLE
0.11757583407233248206...
MATHEMATICA
RealDigits[ N[(4 Pi^6*Log[2]-90 Pi^4*Zeta[3]+1350 Pi^2*Zeta[5]-5715 Pi^2*Zeta[7])/1536, 150]][[1]]
CROSSREFS
KEYWORD
cons,nonn
AUTHOR
Seiichi Kirikami, Sep 01 2011
STATUS
approved
Decimal expansion of 7*zeta(3)/16 + Pi^2*log(2)/8, where zeta is the Riemann zeta function.
+10
0
1, 3, 8, 1, 0, 3, 5, 9, 5, 3, 1, 1, 4, 4, 6, 2, 0, 6, 7, 9, 6, 8, 3, 2, 0, 3, 3, 9, 9, 0, 5, 5, 2, 1, 3, 7, 9, 8, 7, 2, 1, 5, 3, 8, 8, 3, 9, 2, 2, 4, 5, 7, 4, 5, 0, 1, 9, 9, 6, 3, 5, 2, 8, 6, 5, 2, 6, 6, 9, 3, 8, 6, 9, 8, 9, 6, 8, 5, 8, 0, 6, 7, 7, 9, 4, 8, 1, 8, 2, 0, 7, 9, 3, 9, 7, 3, 3, 3, 4, 8, 1, 5, 6
OFFSET
1,2
FORMULA
Equals the absolute value of Integral_{x=0..Pi/2} x*log(cos x) dx.
Equals (Pi/2) * A173623 - A173624.
EXAMPLE
1.38103595311446206796832033990552137987215388392245...
MAPLE
7*Zeta(3)/16 + Pi^2*log(2)/8 ; evalf(%) ;
MATHEMATICA
RealDigits[7*Zeta[3]/16 + Pi^2*Log[2]/8, 10, 120][[1]] (* Amiram Eldar, Aug 05 2024 *)
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
R. J. Mathar, Aug 04 2024
STATUS
approved
Decimal expansion of Pi*(Pi^2*log(2) + 4*log(2)^3 + 6*zeta(3))/48.
+10
0
1, 0, 0, 6, 9, 8, 0, 4, 8, 4, 9, 6, 2, 5, 1, 5, 5, 8, 7, 0, 2, 5, 0, 7, 0, 6, 8, 8, 4, 4, 5, 9, 9, 9, 3, 3, 0, 9, 1, 8, 1, 1, 8, 3, 8, 4, 2, 9, 5, 7, 7, 3, 6, 5, 1, 2, 0, 9, 7, 6, 6, 8, 3, 5, 8, 7, 6, 6, 7, 3, 8, 3, 7, 5, 7, 7, 5, 9, 5, 9, 6, 9, 3, 4, 0, 0, 7, 8, 4, 7, 1, 0, 9, 8, 0, 4, 3, 6, 1, 5, 8, 5
OFFSET
1,4
COMMENTS
Apart from a factor sqrt(Pi)/16 the same as Adamchik's generalized Stirling number [1/2,4].
LINKS
V. S. Adamchik, On Stirling numbers and Euler sums, J. Comput. Appl. Math. 79 (1) (1997) 119-130.
FORMULA
Equals 5F4(1/2,1/2,1/2,1/2,1/2; 3/2,3/2,3/2,3/2; 1) = Sum_{k>= 0} binomial(2k,k)/[2^(2k)*(2k+1)^4].
Equals A196878/6. - R. J. Mathar, Aug 23 2024
EXAMPLE
1.006980484962515...
MAPLE
1/48*Pi*(Pi^2*log(2)+4*log(2)^3+6*Zeta(3)) ; evalf(%) ;
MATHEMATICA
First[RealDigits[Pi*(Pi^2*Log[2] + 4*Log[2]^3 + 6*Zeta[3])/48, 10, 100]] (* Paolo Xausa, Aug 23 2024 *)
CROSSREFS
Cf. A019669 (2F1), A173623 (3F2), A318741 (4F3).
KEYWORD
nonn,cons
AUTHOR
R. J. Mathar, Aug 20 2024
STATUS
approved

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