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A130031 Row sums of triangle A129467. 4
1, 1, -1, 5, -55, 1045, -30305, 1242505, -68337775, 4851982025, -431826400225, 47069077624525, -6166049168812775, 955737621165980125, -172988509431042402625, 36154598471087862148625, -8640949034589999053521375, 2341697188373889743504292625 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

COMMENTS

See the M. Bruschi et al. reference given in A129467.

LINKS

Table of n, a(n) for n=0..17.

FORMULA

a(n)=sum(A129467(n,m),m=0..n), n>=0.

a(n) ~ 2*(-1)^n * cos(sqrt(5)*Pi/2) * n^(2*n) / exp(2*n). - Vaclav Kotesovec, Aug 24 2016

Conjecture: a(n) +(n^2-n-1)*a(n-1)=0. - R. J. Mathar, Jan 21 2018

MATHEMATICA

Table[(-1)^n*Product[k^2-k-1, {k, 1, n}], {n, 0, 20}] (* Vaclav Kotesovec, Aug 24 2016 *)

Table[FullSimplify[(-1)^n * Cos[Sqrt[5]*Pi/2] * Gamma[n+(Sqrt[5]+1)/2] * Gamma[n-(Sqrt[5]-1)/2]/Pi], {n, 0, 20}] (* Vaclav Kotesovec, Aug 24 2016 *)

CROSSREFS

a(n+1), n>=0, also row sums of triangle A130559.

Sequence in context: A006150 A140049 A300589 * A336289 A119399 A177557

Adjacent sequences:  A130028 A130029 A130030 * A130032 A130033 A130034

KEYWORD

sign,easy

AUTHOR

Wolfdieter Lang, May 04 2007

STATUS

approved

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Last modified August 3 20:08 EDT 2020. Contains 336201 sequences. (Running on oeis4.)