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A162645 Numbers m such that A162511(m) = -1. 4
4, 9, 12, 16, 18, 20, 25, 28, 44, 45, 48, 49, 50, 52, 60, 63, 64, 68, 72, 75, 76, 80, 81, 84, 90, 92, 98, 99, 108, 112, 116, 117, 121, 124, 126, 132, 140, 147, 148, 150, 153, 156, 162, 164, 169, 171, 172, 175, 176, 188, 192, 198, 200, 204, 207, 208, 212, 220, 228 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Numbers n where A001222(n)-A001221(n) is odd. - Enrique Pérez Herrero, Jul 07 2012

This sequence has an asymptotic density (1 - A065472/zeta(2))/2 = 0.264159... (Mossinghoff and Trudgian, 2019). - Amiram Eldar, Jul 07 2020

LINKS

Enrique Pérez Herrero, Table of n, a(n) for n = 1..5000

Michael J. Mossinghoff and Timothy S. Trudgian, A tale of two omegas, arXiv:1906.02847 [math.NT], 2019.

MATHEMATICA

Select[Range[10^2], OddQ[PrimeOmega[#]-PrimeNu[#]]&] (* Enrique Pérez Herrero, Jul 07 2012 *)

CROSSREFS

Complement of A162644.

Subsequence of A072587.

Cf. A001221, A001222, A065472, A162643, A162511.

Sequence in context: A162643 A072587 A240112 * A135572 A337103 A312855

Adjacent sequences:  A162642 A162643 A162644 * A162646 A162647 A162648

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Jul 08 2009

STATUS

approved

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Last modified November 30 18:59 EST 2020. Contains 338808 sequences. (Running on oeis4.)