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Revision History for A213387 (Underlined text is an addition; strikethrough text is a deletion.)

Showing entries 1-10 | older changes
A213387 a(n) = 5*2^(n-1) - 2 - 3*n.
(history; published version)
#48 by Michael De Vlieger at Mon Feb 19 12:10:37 EST 2024
STATUS

reviewed

approved

#47 by Joerg Arndt at Mon Feb 19 11:49:25 EST 2024
STATUS

proposed

reviewed

#46 by Joerg Arndt at Mon Feb 19 11:49:12 EST 2024
STATUS

editing

proposed

Discussion
Mon Feb 19 11:49
Joerg Arndt: yes it is
#45 by Joerg Arndt at Mon Feb 19 11:48:46 EST 2024
FORMULA

G.f.: -.: x^2*(2+x) / ( (1-2*x-1)*(x-1-x)^2 ). - R. J. Mathar, Jun 29 2012

STATUS

proposed

editing

#44 by Jon E. Schoenfield at Mon Feb 19 11:27:23 EST 2024
STATUS

editing

proposed

#43 by Jon E. Schoenfield at Mon Feb 19 11:26:43 EST 2024
FORMULA

G.f.: -x^2*(2+x) / () / ( (2*x-1)*(x-1)^2 ). - R. J. Mathar, Jun 29 2012

Discussion
Mon Feb 19 11:27
Jon E. Schoenfield: Is this attempted correction to the g.f. correct?
#42 by Jon E. Schoenfield at Mon Feb 19 11:25:57 EST 2024
FORMULA

a(1)=0, a(2)=2, a(3)=9, a(n)=) = 4*a(n-1)-) - 5*a(n-2)+) + 2*a(n-3); a(1)=0, a(2)=2, a(3). - _)=9. - _Harvey P. Dale_, Sep 28 2012

EXAMPLE

For n=5, m(5,1)=16, m(4,2)=15, m(3,3)=11, m(2,4)=11, m(1,5)=10 gives the sum 63= = 2*A000295(4)+) + A095151(4)=) = 2*11+ + 41.

#41 by Jon E. Schoenfield at Mon Feb 19 11:24:45 EST 2024
NAME

a(n) = 5*2^(n-1)-) - 2- - 3*n.

COMMENTS

Create an array m(i,j) as follows: m(1,j) =) = j*(j-1)/2 in the top row, m(i,1) =() = (i-1)^2 in the left column, and m(i,j)=) = m(i,j-1) + m(i-1,j) recursively in the main body, j>= >= 1, i>= >= 1. The sum of the terms in an antidiagonal is one term in this sequence, a(n) = sumSum_{k=1..n} m(n-k+1,k).

FORMULA

a(n) = A095151(n-1) + 2*A000295(n-1) .).

STATUS

proposed

editing

#40 by Michel Marcus at Mon Feb 19 11:07:32 EST 2024
STATUS

editing

proposed

#39 by Michel Marcus at Mon Feb 19 11:07:29 EST 2024
LINKS

<a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (4,-5,2).

FORMULA

G.f. -.: -x^2*(2+x) / (2*x-1)*(x-1)^2 ). - R. J. Mathar, Jun 29 2012

EXAMPLE

For n=5, m(5,1)=16, m(4,2)=15, m(3,3)=11, m(2,4)=11, m(1,5)=10 gives the sum 63=2*A000295(4)+A095151(4)=2*11+41.

CROSSREFS

Cf. A000295, A095151, A000217, A000290.

STATUS

approved

editing

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Last modified August 29 08:01 EDT 2024. Contains 375510 sequences. (Running on oeis4.)