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Totally multiplicative sequence with a(p) = 8*(p+2) for prime p.
1

%I #12 Oct 19 2023 02:16:57

%S 1,32,40,1024,56,1280,72,32768,1600,1792,104,40960,120,2304,2240,

%T 1048576,152,51200,168,57344,2880,3328,200,1310720,3136,3840,64000,

%U 73728,248,71680,264,33554432,4160,4864,4032,1638400,312,5376,4800,1835008,344,92160,360

%N Totally multiplicative sequence with a(p) = 8*(p+2) for prime p.

%H G. C. Greubel, <a href="/A167309/b167309.txt">Table of n, a(n) for n = 1..1000</a>

%F Multiplicative with a(p^e) = (8*(p+2))^e. If n = Product p(k)^e(k) then a(n) = Product (8*(p(k)+2))^e(k).

%F a(n) = A165829(n) * A166590(n) = 8^bigomega(n) * A166590(n) = 8^A001222(n) * A166590(n).

%t a[1] = 1; a[n_] := (fi = FactorInteger[n]; Times @@ ((fi[[All, 1]] + 2)^fi[[All, 2]])); Table[a[n]*8^PrimeOmega[n], {n, 1, 100}] (* _G. C. Greubel_, Jun 07 2016 *)

%t f[p_, e_] := (8*(p+2))^e; a[1] = 1; a[n_] := Times @@ f @@@ FactorInteger[n]; Array[a, 100] (* _Amiram Eldar_, Oct 19 2023 *)

%Y Cf. A001222, A165829, A166590.

%K nonn,easy,mult

%O 1,2

%A _Jaroslav Krizek_, Nov 01 2009

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Last modified September 19 21:59 EDT 2024. Contains 376015 sequences. (Running on oeis4.)