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 A089692 a(n)=phi(2n)/2^omega(n). 0
 1, 1, 1, 2, 2, 1, 3, 4, 3, 2, 5, 2, 6, 3, 2, 8, 8, 3, 9, 4, 3, 5, 11, 4, 10, 6, 9, 6, 14, 2, 15, 16, 5, 8, 6, 6, 18, 9, 6, 8, 20, 3, 21, 10, 6, 11, 23, 8, 21, 10, 8, 12, 26, 9, 10, 12, 9, 14, 29, 4, 30, 15, 9, 32, 12, 5, 33, 16, 11, 6, 35, 12, 36, 18, 10, 18, 15, 6, 39, 16, 27, 20, 41, 6, 16, 21 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS Here omega(n) means the number of prime factors of n counted without multiplicity. - Harvey P. Dale, Dec 12 2012 LINKS FORMULA a(n)=A062570(n)/A034444(n) Multiplicative with a(2^e) = 2^(e-1) and a(p^e) = (p^e-p^(e-1))/2 for an odd prime p. - Vladeta Jovovic, Jan 15 2004 MATHEMATICA Table[EulerPhi[2n]/2^PrimeNu[n], {n, 90}] (* Harvey P. Dale, Dec 12 2012 *) CROSSREFS Sequence in context: A105809 A091594 A118032 * A066201 A303273 A193820 Adjacent sequences:  A089689 A089690 A089691 * A089693 A089694 A089695 KEYWORD nonn,mult AUTHOR Benoit Cloitre, Jan 06 2004 STATUS approved

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Last modified October 18 17:13 EDT 2019. Contains 328186 sequences. (Running on oeis4.)