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A003980 Möbius transform of A003965. 0
1, 1, 2, 2, 4, 2, 7, 4, 6, 4, 12, 4, 20, 7, 8, 8, 33, 6, 54, 8, 14, 12, 88, 8, 20, 20, 18, 14, 143, 8, 232, 16, 24, 33, 28, 12, 376, 54, 40, 16, 609, 14, 986, 24, 24, 88, 1596, 16, 56, 20, 66, 40, 2583, 18, 48, 28, 108, 143, 4180, 16, 6764, 232, 42, 32, 80, 24, 10945, 66 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..68.

N. J. A. Sloane, Transforms

FORMULA

Multiplicative with a(p^e) = (q-1)q^(e-1) were q = Fib(pi(p)+1) = A000045(A000720(p)+2). - David W. Wilson, Sep 01 2001

MATHEMATICA

a[n_] := If[n == 1, 1, Product[{p, e} = pe; q = Fibonacci[PrimePi[p] + 2]; (q-1) q^(e-1), {pe, FactorInteger[n]}]];

Array[a, 100] (* Jean-François Alcover, Sep 29 2020 *)

CROSSREFS

Sequence in context: A122977 A275870 A321721 * A286369 A132801 A321199

Adjacent sequences:  A003977 A003978 A003979 * A003981 A003982 A003983

KEYWORD

nonn,mult

AUTHOR

Marc LeBrun

EXTENSIONS

More terms from David W. Wilson, Aug 29 2001

STATUS

approved

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Last modified June 16 04:56 EDT 2021. Contains 345056 sequences. (Running on oeis4.)