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 A158110 G.f.: A(x) = exp( Sum_{n>=1} 2^(n^3)*x^n/n ). 2
 1, 2, 130, 44739500, 4611686018516874838, 8507059173023461595807737228465099196, 17552048611426197782986337964292523732529439672780432120964458900 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Conjecture: given q and m are nonnegative integers, then exp( Sum_{n>=1} q^(n^m)*x^n/n ) is a power series in x with integer coefficients. LINKS Table of n, a(n) for n=0..6. EXAMPLE G.f.: A(x) = 1 + 2*x + 130*x^2 + 44739500*x^3 +... log(A(x)) = 2*x + 2^8*x^2/2 + 2^27*x^3/3 + 2^64*x^4/4 +... PROG (PARI) {a(n)=polcoeff(exp(sum(m=1, n+1, 2^(m^3)*x^m/m)+x*O(x^n)), n)} CROSSREFS Cf. A155200. Sequence in context: A218434 A354054 A303445 * A117626 A084549 A142251 Adjacent sequences: A158107 A158108 A158109 * A158111 A158112 A158113 KEYWORD nonn AUTHOR Paul D. Hanna, Mar 19 2009 STATUS approved

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Last modified March 5 03:04 EST 2024. Contains 370537 sequences. (Running on oeis4.)