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A102921
Column 0 of triangle A102920, which equals the matrix square of A102098.
3
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.
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
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Jan 21 2005
STATUS
approved