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A113343
Column 3 of triangle A113340, also equals column 0 of A113340^7.
4
1, 7, 70, 889, 13853, 258146, 5633264, 141487178, 4031806898, 128792484219, 4565493788191, 178051324792642, 7583098790779316, 350435514388561567, 17474323210108996497, 935597107908721785211, 53553176933223851350863
OFFSET
0,2
PROG
(PARI) a(n)=local(A, B); A=matrix(1, 1); A[1, 1]=1; for(m=2, n+4, 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^(2*j-1))[i-j+1, 1])); )); A=B); A[n+4, 4]
CROSSREFS
Cf. A113341 (column 1), A113342 (column 2), A113344 (column 4), A113340.
Sequence in context: A255519 A305966 A226805 * A124566 A141151 A001669
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Nov 08 2005
STATUS
approved