%I #13 Jan 05 2024 23:32:23
%S 1,2,3,6,13,22,53,104,189,420,739,1420,2687,5198,8907,15762,30709,
%T 51322,92765,153932,275181,478560,806515,1334656,2222951,3864914,
%U 6233763,10538622,16896061,27407110,44632877,74032352,117178797
%N "BGK" (reversible, element, unlabeled) transform of 2,2,2,2,...
%H Andrew Howroyd, <a href="/A032061/b032061.txt">Table of n, a(n) for n = 0..1000</a>
%H C. G. Bower, <a href="/transforms2.html">Transforms (2)</a>
%o (PARI) seq(n)=[subst(serlaplace(y^0*p + polcoeff(p,1)),y,1)/2 | p <- Vec(y-1+prod(k=1, n, 1 + x^k*y + O(x*x^n))^2)] \\ _Andrew Howroyd_, Sep 13 2018
%K nonn
%O 0,2
%A _Christian G. Bower_
%E a(0)=1 prepended by _Andrew Howroyd_, Sep 13 2018