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A166652
Totally multiplicative sequence with a(p) = 3p-1 for prime p.
2
1, 5, 8, 25, 14, 40, 20, 125, 64, 70, 32, 200, 38, 100, 112, 625, 50, 320, 56, 350, 160, 160, 68, 1000, 196, 190, 512, 500, 86, 560, 92, 3125, 256, 250, 280, 1600, 110, 280, 304, 1750, 122, 800, 128, 800, 896, 340, 140, 5000, 400, 980
OFFSET
1,2
LINKS
FORMULA
Multiplicative with a(p^e) = (3p-1)^e. If n = Product p(k)^e(k) then a(n) = Product (3*p(k)-1)^e(k).
MATHEMATICA
a[1] = 1; a[n_] := (fi = FactorInteger[n]; Times @@ ((3*fi[[All, 1]] - 1)^fi[[All, 2]])); Table[a[n], {n, 1, 100}] (* G. C. Greubel, May 21 2016 *)
CROSSREFS
Sequence in context: A368484 A346552 A375350 * A286571 A234334 A025623
KEYWORD
nonn,mult
AUTHOR
Jaroslav Krizek, Oct 18 2009
STATUS
approved