A179433 Column 1 of triangle A179430.
1, 9, 405, 121500, 247203171, 3543210805275, 373203783345533355, 299059356226224581923626, 1870707073035678423776605220985, 93075349691648156957700437094276630105
Offset: 0
Keywords
Examples
G.f.: A(x) = 1 + 9*x + 405*x^2 + 121500*x^3 + 247203171*x^4 +...
Programs
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PARI
{a(n)=local(M=matrix(n+2, n+2, r, c, binomial(r*3^(c-2), c-1)), P); P=matrix(n+2, n+2, r, c, binomial((r+1)*3^(c-2), c-1)); (P~*M~^-1)[n+2, 2]}
Comments