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%I #17 Sep 04 2023 01:59:54
%S 1,2,3,3,4,6,5,4,7,8,6,9,7,10,12,5,8,14,9,12,15,12,10,12,13,14,15,15,
%T 11,24,12,6,18,16,20,21,13,18,21,16,14,30,15,18,28,20,16,15,21,26,24,
%U 21,17,30,24,20,27,22,18,36,19,24,35,7,28,36,20,24,30,40,21,28,22,26
%N Inverse Möbius transform of A003963.
%F Multiplicative with a(p^e) = e+1 if p = 2; (q^(e+1)-1)/(q-1) if p > 2; where q = pi(p) = A000720(p). - _David W. Wilson_, Sep 01 2001
%t f[p_, e_] := Module[{q = PrimePi[p]}, (q^(e+1)-1)/(q-1)]; f[2, e_] := e+1; a[n_] := Times @@ f @@@ FactorInteger[n]; a[1] = 1; Array[a, 100] (* _Amiram Eldar_, Sep 04 2023 *)
%Y Cf. A000720, A003963.
%K nonn,easy,mult
%O 1,2
%A _Marc LeBrun_
%E More terms from _David W. Wilson_, Aug 29 2001
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