A113112 Triangle T, read by rows, equal to the matrix 4th power of triangle A113106, which satisfies the recurrence: A113106(n,k) = [A113106^5](n-1,k-1) + [A113106^5](n-1,k).

1, 4, 1, 56, 24, 1, 2704, 1576, 124, 1, 481376, 346624, 39376, 624, 1, 337587520, 284081376, 41686624, 979376, 3124, 1, 978162377600, 927672109184, 165184873376, 5122890624, 24434376, 15624, 1, 12088945462984960

Offset

0,2

Links

Table of n, a(n) for n=0..28.

Example

Triangle begins:
1;
4,1;
56,24,1;
2704,1576,124,1;
481376,346624,39376,624,1;
337587520,284081376,41686624,979376,3124,1;
978162377600,927672109184,165184873376,5122890624,24434376,15624,1;

Prog

(PARI) {T(n, k)=local(M=matrix(n+1, n+1)); for(r=1, n+1, for(c=1, r, M[r, c]=if(r==c, 1, if(c>1, (M^5)[r-1, c-1])+(M^5)[r-1, c]))); return((M^4)[n+1, k+1])}

Crossrefs

Cf. A113106, A113108, A113110.

Sequence in context: A372013 A316159 A370415 * A278578 A368266 A338681

Adjacent sequences: A113109 A113110 A113111 * A113113 A113114 A113115

Keyword

nonn,tabl

Author

Paul D. Hanna, Oct 14 2005

Status

approved