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Multiplicative with a(p^e) = e^3, p prime and e > 0.
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%I #19 Mar 30 2023 02:39:26

%S 1,1,1,8,1,1,1,27,8,1,1,8,1,1,1,64,1,8,1,8,1,1,1,27,8,1,27,8,1,1,1,

%T 125,1,1,1,64,1,1,1,27,1,1,1,8,8,1,1,64,8,8,1,8,1,27,1,27,1,1,1,8,1,1,

%U 8,216,1,1,1,8,1,1,1,216,1,1,8,8,1,1,1,64,64

%N Multiplicative with a(p^e) = e^3, p prime and e > 0.

%H Robert Israel, <a href="/A360970/b360970.txt">Table of n, a(n) for n = 1..10000</a>

%H Vaclav Kotesovec, <a href="/A360970/a360970.jpg">Graph - the asymptotic ratio (10^9 terms)</a>

%F Dirichlet g.f.: zeta(s) * Product_{primes p} (1 + (7*p^(2*s) - 2*p^s + 1) / (p^s*(p^s - 1)^3)).

%F Sum_{k=1..n} a(k) ~ c * n, where c = Product_{primes p} (1 + (7*p^2 - 2*p + 1) / (p*(p-1)^3)) = 109.601930729008995813857898403091253809628920963774227252953...

%F a(n) = A005361(n)^3.

%p f:= proc(n) local t;

%p mul(t^3, t = ifactors(n)[2][..,2]);

%p end proc:

%p map(f, [$1..100]); # _Robert Israel_, Mar 29 2023

%t g[p_, e_] := e^3; a[1] = 1; a[n_] := Times @@ g @@@ FactorInteger[n]; Array[a, 100]

%o (PARI) for(n=1, 100, print1(direuler(p=2, n, (1 - 3*X + 10*X^2 - 3*X^3 + X^4)/(1-X)^4)[n], ", "))

%Y Cf. A005361, A226602, A360969, A361132.

%K nonn,mult

%O 1,4

%A _Vaclav Kotesovec_, Feb 27 2023