%I #9 Oct 26 2019 15:40:18
%S 1,6,29,156,741,3958,19233,103340,513829,2782642,14111035,76987001,
%T 396866211,2179190558,11387537287,62869497136,332264796115,
%U 1842788400972,9831563838105,54737178645869,294362713929617,1644215891925732,8902034364734719,49863044050919951
%N a(n) = Sum_{k=0..n-1} T(n,k) * T(n,k+1), with T given by A026780.
%K nonn
%O 1,2
%A _Clark Kimberling_
%E More terms from _Sean A. Irvine_, Oct 26 2019