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

Author

Paul D. Hanna, Jan 21 2005

Keywords

• nonn

Comments

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

Crossrefs

Cf. A102920, A102098, A102917.

Programs

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,.. */