A166662 Totally multiplicative sequence with a(p) = 4p+1 for prime p.

1, 9, 13, 81, 21, 117, 29, 729, 169, 189, 45, 1053, 53, 261, 273, 6561, 69, 1521, 77, 1701, 377, 405, 93, 9477, 441, 477, 2197, 2349, 117, 2457, 125, 59049, 585, 621, 609, 13689, 149, 693, 689, 15309, 165, 3393, 173, 3645, 3549, 837, 189, 85293, 841, 3969

Offset

1,2

Links

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

Formula

Multiplicative with a(p^e) = (4p+1)^e. If n = Product p(k)^e(k) then a(n) = Product (4*p(k)+1)^e(k).

Mathematica

a[1] = 1; a[n_] := (fi = FactorInteger[n]; Times @@ ((4*fi[[All, 1]] + 1)^fi[[All, 2]])); Table[a[n], {n, 1, 100}] (* G. C. Greubel, May 22 2016 *)

Crossrefs

Sequence in context: A305650 A099580 A258286 * A108748 A116106 A123813

Adjacent sequences: A166659 A166660 A166661 * A166663 A166664 A166665

Keyword

nonn,mult

Author

Jaroslav Krizek, Oct 18 2009

Status

approved