This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A162585 #16 Apr 05 2020 15:53:02
%S A162585 1,2,8,20,114,288,1156,3256,23464,59716,243212,699216,3659988,
%T A162585 10265800,42353168,128163440,1127515970,2858004752,11768578868,
%U A162585 34294832344,180335471424,513911386232,2137413847256,6572758142016,41948816796852
%N A162585 G.f.: A(x) = exp( Sum_{n>=1} C(2n,n)*A006519(n) * x^n/n ), where A006519(n) = highest power of 2 dividing n.
%C A162585 Compare g.f. to the g.f. of the Catalan numbers: exp( Sum_{n>=1} C(2n,n)*x^n/n ), where C(2n,n) form the central binomial coefficients (A000984).
%H A162585 G. C. Greubel, <a href="/A162585/b162585.txt">Table of n, a(n) for n = 0..1000</a>
%e A162585 G.f.: A(x) = 1 + 2*x + 6*x^2 + 10*x^3 + 146*x^4 + 282*x^5 + 826*x^6 + ...
%e A162585 log(A(x)) = 2*x + 12*x^2/2 + 20*x^3/3 + 280*x^4/4 + 252*x^5/5 + 1848*x^6/6 + ... + C(2n,n)*A006519(n)*x^n/n + ...
%t A162585 nmax=50; CoefficientList[Series[Exp[Sum[2^(IntegerExponent[k, 2])*Binomial[2*k, k]*q^k/k, {k,nmax+3}]], {q,0,nmax}], q] (* _G. C. Greubel_, Jul 04 2018 *)
%o A162585 (PARI) {a(n)=local(L=sum(m=1,n,2^valuation(m,2)*binomial(2*m,m)*x^m/m)+x*O(x^n));polcoeff(exp(L),n)}
%Y A162585 Cf. A000108, A000123, A000984, A006519.
%K A162585 nonn
%O A162585 0,2
%A A162585 _Paul D. Hanna_, Jul 06 2009