A003979 - OEIS

A003979

Inverse Möbius transform of A003964.

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

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OFFSET

1,2

LINKS

Table of n, a(n) for n=1..64.

N. J. A. Sloane, Transforms.

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

Cf. A000041, A000720, A003964, A003978.

Sequence in context: A143348 A000203 A324545 * A084250 A090128 A086293

Adjacent sequences: A003976 A003977 A003978 * A003980 A003981 A003982

KEYWORD

nonn,easy,mult

AUTHOR

Marc LeBrun

EXTENSIONS

More terms from Vladeta Jovovic, Dec 01 2001

STATUS

approved