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A102922
Column 1 of triangle A102920, which equals the matrix square of A102098.
2
0, 4, 40, 1128, 61120, 5466320, 735847800, 139910204080, 35858685086352, 11953187179149408, 5037776918810353960, 2623732639426967662648, 1656984556235159516822400, 1248959074762601252295551168
OFFSET
0,2
COMMENTS
Equals the odd bisection of A102917. Triangle A102098 shifts each column up 1 row under matrix cube.
PROG
(PARI) {a(n)=local(A=matrix(2, 2), B); A[1, 1]=1; for (m=2, n+1, B=matrix(m, m); for (i=1, m, for (j=1, i, if(j==i, B[i, j]=j, if(j==1, B[i, j]=(A^3)[i-1, 1], B[i, j]=(A^3)[i-1, j])); )); A=B); return((A^2)[n+1, 2])}
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Jan 21 2005
STATUS
approved