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G.f.: A(x) = Sum_{n>=0} log(1 + 2^n*x/(1-x))^n/n!.
1

%I #6 Apr 04 2023 10:46:43

%S 1,2,8,70,2008,209018,76000040,94978699326,410326957417208,

%T 6211396910763188786,334321755307017208207432,

%U 64835518006826024523658441206,45812575197824183928260946747286552

%N G.f.: A(x) = Sum_{n>=0} log(1 + 2^n*x/(1-x))^n/n!.

%F a(n) = Sum_{k=0..n} binomial(2^k, k) * binomial(n-1, n-k) for n >= 0. - _Paul D. Hanna_, Apr 04 2023

%e G.f.: A(x) = 1 + x + 2*x^2 + 8*x^3 + 70*x^4 + 2008*x^5 +...

%e A(x) = Sum_{n>=0} log(1 + 2^n*x + 2^n*x^2 + 2^n*x^3 + 2^n*x^4 +...)^n/n!.

%e A(x) = 1 + log(1+2x/(1-x)) + log(1+4x/(1-x))^2/2! + log(1+8x/(1-x))^3/3! +...

%o (PARI) {a(n)=polcoeff(sum(m=0, n, log(1+2^m*x/(1-x+x*O(x^n)))^m/m!), n)}

%Y Cf. variants: A159602, A060690.

%K nonn

%O 0,2

%A _Paul D. Hanna_, Sep 16 2010