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%I #7 Jan 04 2023 18:17:11
%S 1,2,5,24,239,4920,206727,17568408,3003763243,1030272816360,
%T 707851744149198,973425618916674288,2678332881795756783639,
%U 14741522294008025924154864,162290544340043699103996962253,3573515596966915773419766367302288,157376160486791180710467411977740266927
%N G.f.: 1 = Sum_{n>=0} a(n)*x^n/(1+x)^(2*2^n).
%C Equals unsigned column 1 of triangle A137156.
%o (PARI) {a(n)=polcoeff(1-sum(k=0, n-1, a(k)*x^k/(1+x+x*O(x^n))^(2^(k+1)) ), n)}
%Y Cf. A137156; A001192, A137158, A137159, A137160.
%K nonn
%O 0,2
%A _Paul D. Hanna_, Jan 24 2008
%E a(15)-a(16) from _Alois P. Heinz_, Jan 04 2023