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%I #7 May 21 2016 22:34:28
%S 1,13,20,169,34,260,48,2197,400,442,76,3380,90,624,680,28561,118,5200,
%T 132,5746,960,988,160,43940,1156,1170,8000,8112,202,8840,216,371293,
%U 1520,1534,1632,67600,258,1716,1800,74698,286,12480,300,12844,13600
%N Totally multiplicative sequence with a(p) = 7p-1 for prime p.
%H G. C. Greubel, <a href="/A166656/b166656.txt">Table of n, a(n) for n = 1..10000</a>
%F 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).
%t 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 *)
%K nonn,mult
%O 1,2
%A _Jaroslav Krizek_, Oct 18 2009