A117266 - OEIS

%I #9 Sep 12 2024 07:50:01

%S 1,2,6,37,497,14033,813857,95996993,22913626241,11034472530177,

%T 10699863490757121,20863301244829828097,81721932792141693585409,

%U 642577422892784159654154241,10136733849914528413869372612609

%N Row sums of triangle A117265.

%F a(n) = Sum_{k=0..n} (2*(n-k))!/((n-k)!*(n-k)!)*2^((n-k)*(n+k-3)/2).

%o (PARI) a(n)=sum(k=0,n,(2*(n-k))!/((n-k)!*(n-k)!)*2^((n-k)*(n+k-3)/2))

%Y Cf. A117265.

%K nonn

%O 0,2

%A _Paul D. Hanna_, Mar 14 2006