login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A102923
Row sums of triangle A102920, which equals the matrix square of A102098.
0
1, 7, 85, 2369, 127796, 11417607, 1536493698, 292107021267, 74862835208823, 24954353268384100, 10517125257007205287, 5477412008465124456814, 3459179319447147792978276, 2607366906177104506271124036
OFFSET
0,2
COMMENTS
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, B[i, j]=(A^3)[i-1, j]); )); A=B); return(sum(k=0, n, (A^2)[n+1, k+1]))}
CROSSREFS
Sequence in context: A368787 A207214 A000686 * A220246 A196257 A296382
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Jan 21 2005
STATUS
approved