A224802 Column 2 of triangle A224798.

1, 4, 16, 192, 2816, 84992, 3223552, 247250944, 23344644096, 4762175799296, 1120173091192832, 644677614732050432, 378488143248684482560, 653528083344895592366080, 949029769901509397631205376, 5192644934824847025023714590720

Offset

0,2

Links

Table of n, a(n) for n=0..15.

Prog

 (PARI) {A224798(n, k)=if(n<k|k<0, 0, if(n==k, 1, if(n==k+1, 2^(n-1), sum(j=k+1, n, A224798(n, j)*A224798(j, k+1) ))))}
{a(n)=A224798(n+2, 2)}
for(n=0, 15, print1(a(n), ", "))

Crossrefs

Cf. A224798, A224799, A224800, A224801.

Sequence in context: A012921 A280468 A366818 * A000513 A088027 A271267

Adjacent sequences: A224799 A224800 A224801 * A224803 A224804 A224805

Keyword

nonn

Author

Paul D. Hanna, Apr 22 2013

Status

approved