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A167018
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Column 2 of triangle T=A167015: a(n) = T(n+2,2) = [T^(n+2)](n-1,0) for n>0 with a(0)=1.
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4
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1, 1, 4, 20, 149, 1491, 18612, 275856, 4699180, 89993827, 1907644760, 44253266889, 1113845999245, 30214252304871, 878483783958444, 27252652393849400, 898540310823301994, 31378570076570865074, 1157108876622296079054
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OFFSET
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0,3
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COMMENTS
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In triangle T=A167015, row n of T equals the initial n terms in column 0 of matrix power T^n, reversed and with an appended '1'.
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LINKS
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PROG
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(PARI) {A167015(n, k)=local(M, N); if(n==k|n==k+1, 1, if(n==k+2, k+2, N=matrix(n, n, r, c, if(r>=c, A167015(r-1, c-1))); M=matrix(n+1, n+1, r, c, if(r>=c, if(r<=n, N[r, c], (N^n)[n-k, 1]))); M[n+1, k+1]))}
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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