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%I #5 Mar 30 2012 18:37:25
%S 1,2,3,6,18,79,463,3396,30073,314037,3796561,52332869,812013163,
%T 14029926801,267461387125,5581705418715,126657160962835,
%U 3106644875467396,81943115662983569,2313753122033185373,69654973411269008826,2227679407193350385775
%N Column 0 of triangle A185624; also, equals row sums of triangle A185620.
%C Triangle A185624 equals the matrix square of triangle R = A185620, which satisfies: R^3 - R^2 + I = R shifted left one column.
%o (PARI) {a(n)=local(A=Mat(1), B); for(m=1, n, B=A^3-A^2+A^0; A=matrix(m+1, m+1); for(i=1, m+1, for(j=1, i, if(i<2|j==i, A[i, j]=1, if(j==1, A[i, j]=1, A[i, j]=B[i-1, j-1]))))); return((A^2)[n+1, 1])}
%Y Cf. A185620, A185624, A185626, A185627, A185628.
%K nonn
%O 0,2
%A _Paul D. Hanna_, Sep 07 2011
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