cp's OEIS Frontend

A101346 a(n) = binomial(2^n, n-1).

%I A101346 #17 Feb 13 2020 01:00:28
%S A101346 1,4,28,560,35960,7624512,5423611200,13161885792000,
%T A101346 110859231254749120,3293259778311548232704,
%U A101346 349928324708588104171703296,134575849279352109587517966790656,189165427620415586720308268784807487488,979739920960712963224129514007339757999308800
%N A101346 a(n) = binomial(2^n, n-1).
%H A101346 Andrew Howroyd, <a href="/A101346/b101346.txt">Table of n, a(n) for n = 1..50</a>
%F A101346 G.f.: A(x) = x*Sum_{n>=0} 2^n*log(1+2^n*x)^n/n!. - _Paul D. Hanna_, Jun 21 2009
%F A101346 a(n) ~ 2^(n*(n-1)) / (n-1)!. - _Vaclav Kotesovec_, Jul 02 2016
%p A101346 seq(binomial(2^n,n-1),n=1..20);
%t A101346 Table[Binomial[2^n,n-1], {n,1,15}] (* _Vaclav Kotesovec_, Jul 02 2016 *)
%o A101346 (PARI) a(n)=binomial(2^n,n-1) \\ _Paul D. Hanna_, Jun 21 2009
%o A101346 (PARI) a(n)=polcoeff(x*sum(k=0,n,2^k*log(1+2^k*x+x*O(x^n))^k/k!),n) \\ _Paul D. Hanna_, Jun 21 2009
%Y A101346 Cf. A014070. - _Paul D. Hanna_, Jun 21 2009
%K A101346 nonn
%O A101346 1,2
%A A101346 _Jorge Coveiro_, Dec 25 2004
%E A101346 Terms a(13) and beyond from _Andrew Howroyd_, Feb 12 2020