A132693 Column 2 of triangle A132690.

1, 1, -3, 22, -250, 3810, -72492, 1649634, -43626510, 1313526375, -44332221175, 1657043432088, -67929461003560, 3029864359322346, -146058681728370600, 7566706624571096610, -419220650458638848514, 24733868801871384287055, -1548237182318766914543100

Offset

0,3

Comments

Triangle T=A132690 is generated from negative powers of itself such that row n+1 of T = row n of T^(-n) with appended '1' for n>=0 with T(0,0)=1.

Links

Table of n, a(n) for n=0..18.

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-2)))[i-1, j]); )); A=B); return( ((A)[n+3, 3]))}

Crossrefs

Cf. A132690; A132691, A132692, A132694.

Sequence in context: A162633 A052677 A136741 * A367845 A361097 A143634

Adjacent sequences: A132690 A132691 A132692 * A132694 A132695 A132696

Keyword

sign

Author

Paul D. Hanna, Aug 25 2007

Status

approved