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 A306831 Expansion of e.g.f. exp(Sum_{k>=1} x^(k^2)*(1 + x^(k^2))/k^2). 4
 1, 1, 3, 7, 31, 111, 601, 2773, 27777, 230401, 2484811, 22999791, 254852863, 2615840527, 29661610161, 321837060301, 5736337960321, 86729871740673, 2360637009669907, 39094827261418711, 883743994410948831, 14306422917625170991, 301121907924200191753 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS FORMULA E.g.f.: Product_{k>=1} (1 - x^k)^((-1)^k*lambda(k)/k), where lambda() is the Liouville function (A008836). MATHEMATICA nmax = 23; CoefficientList[Series[Exp[Sum[x^(k^2) (1 + x^(k^2))/k^2, {k, 1, nmax}]], {x, 0, nmax}], x] Range[0, nmax]! nmax = 23; CoefficientList[Series[Product[(1 - x^k)^((-1)^k LiouvilleLambda[k]/k), {k, 1, nmax}], {x, 0, nmax}], x] Range[0, nmax]! CROSSREFS Cf. A008836, A053866, A205801, A308381. Sequence in context: A132153 A002357 A173062 * A105765 A061095 A103901 Adjacent sequences:  A306828 A306829 A306830 * A306832 A306833 A306834 KEYWORD nonn AUTHOR Ilya Gutkovskiy, May 23 2019 STATUS approved

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Last modified June 13 04:17 EDT 2021. Contains 344980 sequences. (Running on oeis4.)