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A003976 Möbius transform of A003963 (with alternate 0's omitted). 0
1, 1, 2, 3, 2, 4, 5, 2, 6, 7, 3, 8, 6, 4, 9, 10, 4, 6, 11, 5, 12, 13, 4, 14, 12, 6, 15, 8, 7, 16, 17, 6, 10, 18, 8, 19, 20, 6, 12, 21, 8, 22, 12, 9, 23, 15, 10, 14, 24, 8, 25, 26, 6, 27, 28, 11, 29, 16, 10, 18, 20, 12, 18, 30, 13, 31, 21, 8, 32, 33, 14, 20, 18, 12, 34, 35, 12, 20 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..78.

N. J. A. Sloane, Transforms

FORMULA

Multiplicative with a(p^e) = (q-1)q^(e-1) where q = pi(p) = A000720(p). - David W. Wilson, Sep 01 2001

EXAMPLE

The Möbius transform begins 1,0,1,0,2,0,3,0,2,0,4,0,5,0,2,0,6,0,7,0,...

PROG

(PARI) a(n) = {my(f=factor(2*n-1)); for (i=1, #f~, q = primepi(f[i, 1]); f[i, 1] = (q-1)*q^(f[i, 2]-1); f[i, 2] = 1); factorback(f); } \\ Michel Marcus, Feb 27 2015

CROSSREFS

Cf. A003963.

Sequence in context: A136181 A265110 A304742 * A252371 A275817 A286533

Adjacent sequences:  A003973 A003974 A003975 * A003977 A003978 A003979

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 March 19 15:02 EDT 2019. Contains 321330 sequences. (Running on oeis4.)