login
A166653
Totally multiplicative sequence with a(p) = 4p-1 for prime p.
2
1, 7, 11, 49, 19, 77, 27, 343, 121, 133, 43, 539, 51, 189, 209, 2401, 67, 847, 75, 931, 297, 301, 91, 3773, 361, 357, 1331, 1323, 115, 1463, 123, 16807, 473, 469, 513, 5929, 147, 525, 561, 6517, 163, 2079, 171, 2107, 2299, 637, 187, 26411, 729, 2527
OFFSET
1,2
LINKS
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 21 2016 *)
CROSSREFS
Sequence in context: A086828 A117392 A105867 * A057290 A003599 A018508
KEYWORD
nonn,mult
AUTHOR
Jaroslav Krizek, Oct 18 2009
STATUS
approved