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'.

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.

Links

Table of n, a(n) for n=0..17.

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

Adjacent sequences: A121412 A121413 A121414 * A121416 A121417 A121418

Keyword

nonn

Author

Paul D. Hanna, Aug 22 2006

Status

approved