A113376 Column 1 of triangle A113374, also equals column 0 of A113381^4.

1, 8, 84, 1296, 27850, 784146, 27630378, 1177691946, 59169833470, 3434258845248, 226594550768662, 16775755397765720, 1378646430074005827, 124636321499378130839, 12300850874338422058685

Offset

0,2

Links

Table of n, a(n) for n=0..14.

Formula

A113374 equals the matrix square of A113370, which has the property: column k of A113370^2 = column 0 of A113381^(3*k+1) for k>=0.

Prog

(PARI) a(n)=local(A, B); A=Mat(1); for(m=2, n+2, B=matrix(m, m); for(i=1, m, for(j=1, i, if(i<3 || j==i || j>m-1, B[i, j]=1, if(j==1, B[i, 1]=1, B[i, j]=(A^(3*j-2))[i-j+1, 1])); )); A=B); (A^2)[n+2, 2]

Crossrefs

Cf. A113374, A113375 (column 0), A113377 (column 2).

Sequence in context: A052659 A346684 A350264 * A205311 A258338 A245197

Adjacent sequences: A113373 A113374 A113375 * A113377 A113378 A113379

Keyword

nonn

Author

Paul D. Hanna, Nov 14 2005

Status

approved