A105557 - OEIS

%I #3 Mar 30 2012 18:36:45

%S 1,2,4,10,32,128,626,3681,25574,206402,1908996,20024149,236142157,

%T 3106393358,45265833590,726249472784,12761749378320,244453274012442,

%U 5082582988294164,114258645210526486,2767462674168199303

%N Row sums of triangle A105556, in which column n equals the row sums of A001263^n, which is the n-th matrix power of the Narayana triangle A001263.

%o (PARI) {a(n)=local(N=matrix(n+1,n+1,m,j,if(m>=j, binomial(m-1,j-1)*binomial(m,j-1)/j))); sum(k=0,n,sum(j=0,n-k,(N^k)[n-k+1,j+1]))}

%Y Cf. A001263, A105556.

%K nonn

%O 0,2

%A _Paul D. Hanna_, Apr 14 2005