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 A003978 Möbius transform of A003964. 1
 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, 55, 8, 76, 16, 20, 21, 24, 12, 100, 29, 28, 16, 134, 12, 175, 20, 24, 41, 230, 16, 42, 20, 42, 28, 296, 18, 40, 24, 58, 55, 384, 16, 489, 76, 36, 32, 56, 20, 626, 42, 82, 24, 791, 24 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS Table of n, a(n) for n=1..72. FORMULA 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 MATHEMATICA 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 *) CROSSREFS Cf. A000041, A000720, A003964, A003979. Sequence in context: A152455 A293484 A000010 * A122645 A122646 A028496 Adjacent sequences: A003975 A003976 A003977 * A003979 A003980 A003981 KEYWORD nonn,easy,mult AUTHOR Marc LeBrun EXTENSIONS More terms from David W. Wilson, Aug 29 2001 STATUS approved

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Last modified December 2 09:50 EST 2023. Contains 367517 sequences. (Running on oeis4.)