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Row sums of triangle A105615.
1

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

%S 1,3,15,107,991,11203,148879,2270027,39041151,747704963,15784630159,

%T 364256650027,9124264794271,246600188525123,7153677209063439,

%U 221729176945261067,7313478624348963391,255786689421734222083

%N Row sums of triangle A105615.

%o (PARI) {a(n)=if(n<0,0,sum(k=0,n,(matrix(n+1,n+1,m,j,if(m>=j,if(m==j,1,if(m==j+1,-2*j, polcoeff(1/sum(i=0,m-j,(2*i)!/i!/2^i*x^i)+O(x^m),m-j)))))^-1)[n+1,k+1]))}

%Y Cf. A105615.

%K nonn

%O 0,2

%A _Paul D. Hanna_, Apr 16 2005