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A320235 G.f.: Product_{k>=1, j>=1} (1 + x^(k*j))^2. 4

%I

%S 1,2,5,12,24,48,94,172,310,550,946,1602,2679,4394,7123,11424,18082,

%T 28344,44039,67754,103412,156660,235489,351602,521650,768998,1127100,

%U 1642946,2381929,3436028,4932998,7049004,10028422,14207122,20044327,28169528,39439899

%N G.f.: Product_{k>=1, j>=1} (1 + x^(k*j))^2.

%C Self-convolution of A107742.

%H Vaclav Kotesovec, <a href="/A320235/b320235.txt">Table of n, a(n) for n = 0..10000</a>

%F Conjecture: log(a(n)) ~ Pi*sqrt(n*log(n)/3).

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

%Y Cf. A107742, A280451, A320236.

%K nonn

%O 0,2

%A _Vaclav Kotesovec_, Oct 08 2018

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Last modified February 26 05:19 EST 2020. Contains 332276 sequences. (Running on oeis4.)