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 A269154 Expansion of Product_{k>=1} (1 + k*x^k)/(1 + 2*x^k). 2

%I #9 Feb 20 2016 09:05:35

%S 1,-1,2,-3,9,-13,31,-53,118,-210,452,-866,1793,-3493,7119,-13992,

%T 28257,-56253,113035,-225318,451745,-901870,1805976,-3609701,7222075,

%U -14439594,28887060,-57763494,115540784,-231066845,462154358,-924282660,1848598423,-3697142099

%N Expansion of Product_{k>=1} (1 + k*x^k)/(1 + 2*x^k).

%H Vaclav Kotesovec, <a href="/A269154/b269154.txt">Table of n, a(n) for n = 0..3300</a>

%F a(n) ~ c * (-2)^n, where c = Product_{k>=1} ((-2)^k + k)/((-2)^k - 1) = 0.4304067090888734207149852218007129877370867778815471457548443780472...

%t nmax = 50; CoefficientList[Series[Product[(1+k*x^k)/(1+2*x^k), {k, 1, nmax}], {x, 0, nmax}], x]

%Y Cf. A022629, A269144, A269153, A269155.

%K sign

%O 0,3

%A _Vaclav Kotesovec_, Feb 20 2016

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Last modified June 9 13:49 EDT 2023. Contains 363180 sequences. (Running on oeis4.)