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A308398 Expansion of e.g.f. exp(Sum_{k>=1} x^(k^2)*(x^(k^2) - 1)/k^2). 2

%I #6 May 25 2019 02:29:06

%S 1,-1,3,-7,19,-51,61,167,6777,-107929,1650691,-17839911,157217083,

%T -1229269627,6185945949,-3251776921,-1151787785999,10138302541647,

%U 532690324952707,-14122245788830279,443912721023736291,-7480012715591067331,115775303074594208893,-1392396864130912381017

%N Expansion of e.g.f. exp(Sum_{k>=1} x^(k^2)*(x^(k^2) - 1)/k^2).

%F E.g.f.: Product_{k>=1} 1/(1 + x^k)^(lambda(k)/k), where lambda() is the Liouville function (A008836).

%t nmax = 23; CoefficientList[Series[Exp[Sum[x^(k^2) (x^(k^2) - 1)/k^2, {k, 1, nmax}]], {x, 0, nmax}], x] Range[0, nmax]!

%t nmax = 23; CoefficientList[Series[Product[1/(1 + x^k)^(LiouvilleLambda[k]/k), {k, 1, nmax}], {x, 0, nmax}], x] Range[0, nmax]!

%Y Cf. A008836, A118208, A190585, A205801, A306831, A308396, A308397.

%K sign

%O 0,3

%A _Ilya Gutkovskiy_, May 24 2019

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Last modified April 24 07:01 EDT 2024. Contains 371920 sequences. (Running on oeis4.)