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A166654
Totally multiplicative sequence with a(p) = 5p-1 for prime p.
2
1, 9, 14, 81, 24, 126, 34, 729, 196, 216, 54, 1134, 64, 306, 336, 6561, 84, 1764, 94, 1944, 476, 486, 114, 10206, 576, 576, 2744, 2754, 144, 3024, 154, 59049, 756, 756, 816, 15876, 184, 846, 896, 17496, 204, 4284, 214, 4374, 4704, 1026, 234, 91854, 1156
OFFSET
1,2
LINKS
FORMULA
Multiplicative with a(p^e) = (5p-1)^e. If n = Product p(k)^e(k) then a(n) = Product (5*p(k)-1)^e(k).
MATHEMATICA
a[1] = 1; a[n_] := (fi = FactorInteger[n]; Times @@ ((5*fi[[All, 1]] - 1)^fi[[All, 2]])); Table[a[n], {n, 1, 100}] (* G. C. Greubel, May 21 2016 *)
CROSSREFS
Sequence in context: A272545 A272009 A298754 * A348318 A370674 A373330
KEYWORD
nonn,mult
AUTHOR
Jaroslav Krizek, Oct 18 2009
STATUS
approved