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%I #3 Mar 30 2012 18:36:51
%S 1,4,33,586,23299,2166800,490872957,280082001078,412989850899863,
%T 1604627387895595612,16673986511766782602033,
%U 468802076619022792385223170,35999655498002937223238590342603
%N Column 1 of triangle A113084, which satisfies the recurrence: A113084(n,k) = [A113084^3](n-1,k-1) + [A113084^3](n-1,k).
%o (PARI) {a(n)=local(M=matrix(n+1,n+1));for(r=1,n+1, for(c=1,r, M[r,c]=if(r==c,1,if(c>1,(M^3)[r-1,c-1])+(M^3)[r-1,c]))); return(if(n<1,0,M[n+1,2]))}
%Y Cf. A113084.
%K nonn
%O 1,2
%A _Paul D. Hanna_, Oct 14 2005