A111779 Sixth column (m=5) of unsigned triangle A111595.

1, 30, 651, 12600, 235494, 4396140, 83471850, 1627358040, 32754696975, 682573101210, 14749179169725, 330654317994000, 7691170398011100, 185559161386599000, 4641068950134516900, 120256269348313098000

Offset

5,2

Links

Table of n, a(n) for n=5..20.

Formula

E.g.f. (1/sqrt(1-x^2))*((x/(1-x))^5)/5!.

a(n)=(n!/5!)*sum(binomial(2*k, k)*binomial(n-2*k-1, 4)/(4^k), k=0..floor((n-5)/2)), n>=5.

Conjecture: +(-n+5)*a(n) +5*n*a(n-1) +n*(n-1)^2*a(n-2)=0. - R. J. Mathar, Jun 08 2016

Crossrefs

Sequence in context: A353115 A136661 A264849 * A075473 A051563 A152499

Adjacent sequences: A111776 A111777 A111778 * A111780 A111781 A111782

Keyword

nonn,easy

Author

Wolfdieter Lang, Aug 23 2005

Status

approved