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Totally multiplicative sequence with a(p) = 8p-1 for prime p.
1

%I #7 May 21 2016 22:34:35

%S 1,15,23,225,39,345,55,3375,529,585,87,5175,103,825,897,50625,135,

%T 7935,151,8775,1265,1305,183,77625,1521,1545,12167,12375,231,13455,

%U 247,759375,2001,2025,2145,119025,295,2265,2369,131625,327,18975,343,19575

%N Totally multiplicative sequence with a(p) = 8p-1 for prime p.

%H G. C. Greubel, <a href="/A166657/b166657.txt">Table of n, a(n) for n = 1..10000</a>

%F Multiplicative with a(p^e) = (8p-1)^e. If n = Product p(k)^e(k) then a(n) = Product (8*p(k)-1)^e(k).

%t a[1] = 1; a[n_] := (fi = FactorInteger[n]; Times @@ ((8*fi[[All, 1]] - 1)^fi[[All, 2]])); Table[a[n], {n, 1, 100}] (* _G. C. Greubel_, May 21 2016 *)

%K nonn,mult

%O 1,2

%A _Jaroslav Krizek_, Oct 18 2009