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A166630
Totally multiplicative sequence with a(p) = 9p for prime p.
1
1, 18, 27, 324, 45, 486, 63, 5832, 729, 810, 99, 8748, 117, 1134, 1215, 104976, 153, 13122, 171, 14580, 1701, 1782, 207, 157464, 2025, 2106, 19683, 20412, 261, 21870, 279, 1889568, 2673, 2754, 2835, 236196, 333, 3078, 3159, 262440, 369, 30618, 387
OFFSET
1,2
LINKS
FORMULA
Multiplicative with a(p^e) = (9p)^e.
If n = Product p(k)^e(k) then a(n) = Product (9*p(k))^e(k).
a(n) = n * A165830(n) = n * 9^bigomega(n) = n * 9^A001222(n).
Dirichlet g.f.: Product_{p prime} 1 / (1 - 9 * p^(1 - s)). - Ilya Gutkovskiy, Oct 30 2019
MATHEMATICA
Table[n*9^PrimeOmega[n], {n, 1, 100}] (* G. C. Greubel, May 19 2016 *)
CROSSREFS
Sequence in context: A038632 A138336 A349485 * A154920 A094224 A128858
KEYWORD
nonn,mult
AUTHOR
Jaroslav Krizek, Oct 18 2009
STATUS
approved