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A113372
Column 2 of triangle A113370, also equals column 0 of A113370^7.
3
1, 7, 91, 1722, 43764, 1415799, 56096733, 2644883675, 145131435225, 9107198292451, 644373208531066, 50814103000624929, 4423148359685316443, 421540670702940409866, 43680252604560889074884
OFFSET
0,2
COMMENTS
Column k of A113370 = column 0 of A113370^(3*k+1) for k>=0.
PROG
(PARI) a(n)=local(A, B); A=Mat(1); for(m=2, n+3, 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[n+3, 3]
CROSSREFS
Cf. A113370, A113371 (column 1), A113373 (column 3).
Sequence in context: A234570 A133307 A151833 * A131940 A008542 A121940
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Nov 13 2005
STATUS
approved