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A003979
Inverse Möbius transform of A003964.
1
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, 48, 40, 56, 57, 72, 78, 63, 48, 69, 48, 91, 102, 93, 64, 90, 136, 96, 177, 84, 78, 129, 232, 124, 57, 93, 92, 112, 298, 120, 72, 120, 124, 171, 386, 168, 491, 234, 104, 127
OFFSET
1,2
LINKS
FORMULA
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
MATHEMATICA
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 *)
CROSSREFS
KEYWORD
nonn,easy,mult
AUTHOR
EXTENSIONS
More terms from Vladeta Jovovic, Dec 01 2001
STATUS
approved