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%I #14 Jun 26 2022 02:15:12
%S 2,8,12,64,20,576,28,1024,216,1600,44,110592,52,3136,3600,32768,68,
%T 373248,76,512000,7056,7744,92,84934656,1000,10816,11664,1404928,116,
%U 207360000,124,2097152,17424,18496,19600,5159780352,148,23104,24336,655360000,164
%N Product of the even divisors of 2n.
%H Robert Israel, <a href="/A126192/b126192.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = 2^A000005(n) * A007955(n). - _Robert Israel_, Feb 01 2019
%p seq(mul(2*t,t=numtheory:-divisors(n)),n=1..100); # _Robert Israel_, Feb 01 2019
%t Table[Times@@Select[Divisors[2n],EvenQ],{n,50}] (* _Harvey P. Dale_, Jul 19 2011 *)
%t a[n_] := 2^(d = DivisorSigma[0, n]) * n^(d/2); Array[a, 100] (* _Amiram Eldar_, Jun 26 2022 *)
%Y Cf. A000005, A007955, A136655, A125911.
%K nonn
%O 1,1
%A _N. J. A. Sloane_, Jul 14 2008