A166625 - OEIS

A166625

Totally multiplicative sequence with a(p) = 4p for prime p.

1, 8, 12, 64, 20, 96, 28, 512, 144, 160, 44, 768, 52, 224, 240, 4096, 68, 1152, 76, 1280, 336, 352, 92, 6144, 400, 416, 1728, 1792, 116, 1920, 124, 32768, 528, 544, 560, 9216, 148, 608, 624, 10240, 164, 2688, 172, 2816, 2880, 736, 188, 49152, 784, 3200

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OFFSET

1,2

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..10000

FORMULA

Multiplicative with a(p^e) = (4p)^e.

If n = Product p(k)^e(k) then a(n) = Product (4*p(k))^e(k).

a(n) = n * A165825(n) = n * 4^bigomega(n) = n * 4^A001222(n).

Dirichlet g.f.: Product_{p prime} 1 / (1 - 4 * p^(1 - s)). - Ilya Gutkovskiy, Oct 30 2019

MATHEMATICA

Table[n 4^PrimeOmega[n], {n, 50}] (* Harvey P. Dale, Jan 20 2014 *)