%I #11 Oct 24 2017 09:06:54
%S 1,4,28,256,2848,37024,547936,9064192,165339904,3290839552,
%T 70870959616,1640130678784,40555349598208,1066271901822976,
%U 29684252411219968,871864036043259904,26931181039027879936,872418396180001718272,29564373329109844885504
%N E.g.f.: exp(2*(1/(1-x)^2 - 1)).
%H Seiichi Manyama, <a href="/A294189/b294189.txt">Table of n, a(n) for n = 0..427</a>
%o (PARI) N=66; x='x+O('x^N); Vec(serlaplace(exp(2*(1/(1-x)^2-1))))
%Y Column k=2 of A294188.
%Y Cf. A136658.
%K nonn
%O 0,2
%A _Seiichi Manyama_, Oct 24 2017