A126192 Product of the even divisors of 2n.

2, 8, 12, 64, 20, 576, 28, 1024, 216, 1600, 44, 110592, 52, 3136, 3600, 32768, 68, 373248, 76, 512000, 7056, 7744, 92, 84934656, 1000, 10816, 11664, 1404928, 116, 207360000, 124, 2097152, 17424, 18496, 19600, 5159780352, 148, 23104, 24336, 655360000, 164

Offset

1,1

Links

Robert Israel, Table of n, a(n) for n = 1..10000

Formula

a(n) = 2^A000005(n) * A007955(n). - Robert Israel, Feb 01 2019

Maple

seq(mul(2*t, t=numtheory:-divisors(n)), n=1..100); # Robert Israel, Feb 01 2019

Mathematica

Table[Times@@Select[Divisors[2n], EvenQ], {n, 50}] (* Harvey P. Dale, Jul 19 2011 *)
a[n_] := 2^(d = DivisorSigma[0, n]) * n^(d/2); Array[a, 100] (* Amiram Eldar, Jun 26 2022 *)

Crossrefs

Cf. A000005, A007955, A136655, A125911.

Sequence in context: A013190 A176968 A308935 * A272720 A331459 A330816

Adjacent sequences: A126189 A126190 A126191 * A126193 A126194 A126195

Keyword

nonn

Author

N. J. A. Sloane, Jul 14 2008

Status

approved