A111782 Ninth column (m=8) of unsigned triangle A111595.

1, 72, 3285, 122760, 4138695, 132046200, 4096887795, 125691766200, 3854667766950, 119027264756400, 3719190784859550, 118004440103550000, 3811105656937829250, 125500234402721178000, 4218813452749267622250

Offset

8,2

Links

Table of n, a(n) for n=8..22.

Formula

E.g.f. (1/sqrt(1-x^2))*((x/(1-x))^8)/8!.

a(n)=(n!/8!)*sum(binomial(2*k, k)*binomial(n-2*k-1, 7)/(4^k), k=0..floor((n-8)/2)), n>=8.

Mathematica

Drop[With[{nn=30}, CoefficientList[Series[1/Sqrt[1-x^2] (x/(1-x))^8/8!, {x, 0, nn}], x] Range[ 0, nn]!], 8] (* Harvey P. Dale, Nov 17 2022 *)

Crossrefs

Sequence in context: A004389 A111598 A116312 * A060507 A238772 A225831

Adjacent sequences: A111779 A111780 A111781 * A111783 A111784 A111785

Keyword

nonn,easy

Author

Wolfdieter Lang, Aug 23 2005

Status

approved