A166656 Totally multiplicative sequence with a(p) = 7p-1 for prime p.

1, 13, 20, 169, 34, 260, 48, 2197, 400, 442, 76, 3380, 90, 624, 680, 28561, 118, 5200, 132, 5746, 960, 988, 160, 43940, 1156, 1170, 8000, 8112, 202, 8840, 216, 371293, 1520, 1534, 1632, 67600, 258, 1716, 1800, 74698, 286, 12480, 300, 12844, 13600

Offset

1,2

Links

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

Formula

Multiplicative with a(p^e) = (7p-1)^e. If n = Product p(k)^e(k) then a(n) = Product (7*p(k)-1)^e(k).

Mathematica

a[1] = 1; a[n_] := (fi = FactorInteger[n]; Times @@ ((7*fi[[All, 1]] - 1)^fi[[All, 2]])); Table[a[n], {n, 1, 100}] (* G. C. Greubel, May 21 2016 *)

Crossrefs

Sequence in context: A132946 A278470 A066515 * A346401 A230498 A260747

Adjacent sequences: A166653 A166654 A166655 * A166657 A166658 A166659

Keyword

nonn,mult

Author

Jaroslav Krizek, Oct 18 2009

Status

approved