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%I #15 Jan 13 2025 06:36:40
%S 1,64,2144,49920,905840,13627264,176638592,2025205248,20930373880,
%T 197788352320,1728062919232,14083242424576,107837287452608,
%U 780481475916160,5366307146732800,35202669371599360,221142159585764508,1334633003840266624,7760187771579170400
%N G.f.: Product_{m>=1} 1/(1-x^m)^64.
%H Alois P. Heinz, <a href="/A082559/b082559.txt">Table of n, a(n) for n = 0..1000</a>
%H <a href="/index/Pro#1mxtok">Index entries for expansions of Product_{k >= 1} (1-x^k)^m</a>
%p a:= proc(n) option remember; `if`(n=0, 1, add(
%p numtheory[sigma](j)*a(n-j), j=1..n)*64/n)
%p end:
%p seq(a(n), n=0..25); # _Alois P. Heinz_, Mar 12 2015
%t a[n_] := a[n] = If[n == 0, 1, Sum[DivisorSigma[1, j]*a[n-j], {j, 1, n}]*64/n]; Table[a[n], {n, 0, 25}] (* _Jean-François Alcover_, Jan 13 2025, after _Alois P. Heinz_ *)
%Y Cf. 64th column of A144064.
%K nonn,changed
%O 0,2
%A _N. J. A. Sloane_, May 04 2003