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A003979 Inverse Möbius transform of A003964. 1

%I #20 Sep 04 2023 02:01:39

%S 1,3,4,7,6,12,8,15,13,18,12,28,16,24,24,31,23,39,31,42,32,36,43,60,31,

%T 48,40,56,57,72,78,63,48,69,48,91,102,93,64,90,136,96,177,84,78,129,

%U 232,124,57,93,92,112,298,120,72,120,124,171,386,168,491,234,104,127

%N Inverse Möbius transform of A003964.

%H N. J. A. Sloane, <a href="/transforms.txt">Transforms</a>.

%F Multiplicative with a(p^e) = (q^(e+1)-1)/(q-1) where q = partition(pi(p)+1) = A000041(A000720(p)+1). - _David W. Wilson_, Sep 01 2001

%t f[p_, e_] := Module[{q = PartitionsP[PrimePi[p] + 1]}, (q^(e+1)-1)/(q-1)]; a[n_] := Times @@ f @@@ FactorInteger[n]; a[1] = 1; Array[a, 100] (* _Amiram Eldar_, Sep 04 2023 *)

%Y Cf. A000041, A000720, A003964, A003978.

%K nonn,easy,mult

%O 1,2

%A _Marc LeBrun_

%E More terms from _Vladeta Jovovic_, Dec 01 2001

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Last modified April 20 11:40 EDT 2024. Contains 371838 sequences. (Running on oeis4.)