A102921 Column 0 of triangle A102920, which equals the matrix square of A102098.

1, 3, 36, 1036, 56355, 5045370, 679409158, 129195427716, 33114233390505, 11038606786054201, 4652371578279864792, 2423023045813285312020, 1530233703568825263174101, 1153422053136775523883308988

Offset

0,2

Comments

Equals the bisection of A102917. Triangle A102098 shifts each column up 1 row under matrix cube.

Links

Table of n, a(n) for n=0..13.

Prog

(PARI) {a(n)=if(n==0, 2, polcoeff(2-sum(k=0, n-1, a(k)*x^k*prod(j=2, k\2+2, 1-j*x +x*O(x^n))), n))} /* at even-indices n=0, 2, 4, .. */

Crossrefs

Cf. A102920, A102098, A102917.

Sequence in context: A132912 A303866 A126447 * A265475 A233197 A300770

Adjacent sequences: A102918 A102919 A102920 * A102922 A102923 A102924

Keyword

nonn

Author

Paul D. Hanna, Jan 21 2005

Status

approved