login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

Expansion of Product_{k>=1} ((1 + (2^k*x)^k)/(1 - (2^k*x)^k))^(1/2^k).
4

%I #14 Apr 25 2018 05:59:55

%S 1,2,10,148,8502,2114924,2151771524,8800410198536,144132802083312550,

%T 9445021284412120235340,2475898969479166225559648172,

%U 2596153381122039693822323043973720,10889040933791649565507987988056678914620

%N Expansion of Product_{k>=1} ((1 + (2^k*x)^k)/(1 - (2^k*x)^k))^(1/2^k).

%H Seiichi Manyama, <a href="/A303440/b303440.txt">Table of n, a(n) for n = 0..58</a>

%F a(n) ~ 2^(n^2 - n + 1). - _Vaclav Kotesovec_, Apr 25 2018

%o (PARI) N=20; x='x+O('x^N); Vec(prod(k=1, N, ((1+(2^k*x)^k)/(1-(2^k*x)^k))^(1/2^k)))

%Y Cf. A303307, A303361, A303381, A303441.

%K nonn

%O 0,2

%A _Seiichi Manyama_, Apr 24 2018