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A003978 Möbius transform of A003964. 1

%I #17 Sep 04 2023 02:01:25

%S 1,1,2,2,4,2,6,4,6,4,10,4,14,6,8,8,21,6,29,8,12,10,41,8,20,14,18,12,

%T 55,8,76,16,20,21,24,12,100,29,28,16,134,12,175,20,24,41,230,16,42,20,

%U 42,28,296,18,40,24,58,55,384,16,489,76,36,32,56,20,626,42,82,24,791,24

%N Möbius transform of A003964.

%F Multiplicative with a(p^e) = (q-1)q^(e-1) were 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-1)*q^(e-1)]; a[n_] := Times @@ f @@@ FactorInteger[n]; a[1] = 1; Array[a, 100] (* _Amiram Eldar_, Sep 04 2023 *)

%Y Cf. A000041, A000720, A003964, A003979.

%K nonn,easy,mult

%O 1,3

%A _Marc LeBrun_

%E More terms from _David W. Wilson_, Aug 29 2001

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Last modified June 10 01:53 EDT 2024. Contains 373251 sequences. (Running on oeis4.)