A121419 Column 2 of triangle A121416.

1, 2, 11, 101, 1305, 21745, 443329, 10679494, 296547736, 9319259500, 326788327650, 12643827604842, 534889691765631, 24555735428777265, 1215611513578215355, 64542477563559758310, 3658333757447085090365

Offset

0,2

Comments

A121416 is the matrix square of triangle A121412; row n of triangle T=A121412 equals row (n-1) of T^(n+1) with an appended '1'.

Links

Table of n, a(n) for n=0..16.

Prog

(PARI) {a(n)=local(A=Mat(1), B); for(m=1, n+3, 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^2)[n+3, 3])}

Crossrefs

Cf. A121416 (triangle); other columns: A121417, A121418.

Sequence in context: A069663 A241100 A337017 * A099701 A089393 A069664

Adjacent sequences: A121416 A121417 A121418 * A121420 A121421 A121422

Keyword

nonn

Author

Paul D. Hanna, Aug 22 2006

Status

approved