login
A121415
Column 3 of triangle A121412, in which row n of T=A121412 equals row (n-1) of T^(n+1) with an appended '1'.
3
1, 1, 6, 63, 924, 17226, 387567, 10182744, 305379129, 10280074116, 383492465902, 15692864353299, 698622377024472, 33604795914668178, 1736477536255603281, 95918139377302294980, 5639487915973132301793, 351611645300506492405623
OFFSET
0,3
COMMENTS
Also equals column 5 of triangle A101479.
PROG
(PARI) {a(n)=local(A=Mat(1), B); for(m=1, n+4, B=matrix(m, m); for(i=1, m, for(j=1, i, if(j==i, B[i, j]=1, B[i, j]=(A^i)[i-1, j]); )); A=B); return((A^1)[n+4, 4])}
CROSSREFS
Cf. A121412 (triangle); other columns: A101483, A121413, A121414; A101479 (triangle).
Sequence in context: A132078 A113669 A340912 * A227278 A295267 A098342
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Aug 22 2006
STATUS
approved