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Column 0 of triangle A185628; also, equals row sums of triangle A185624.
3

%I #7 Mar 30 2012 18:37:26

%S 1,3,6,16,60,305,1988,15951,153171,1722693,22296396,327270440,

%T 5381716953,98134088419,1967105567802,43024511648982,1020235144731236,

%U 26083065249549660,715430961891290714,20962974995245684878,653654392800091507791,21615444263990028093227

%N Column 0 of triangle A185628; also, equals row sums of triangle A185624.

%C Triangle A185628 equals the matrix cube 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+1, 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^3)[n+1, 1])}

%Y Cf. A185620, A185628, A185630, A185631.

%K nonn

%O 0,2

%A _Paul D. Hanna_, Sep 07 2011