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A175859 a(n) = numbers k in increasing order such that A175856(m) = k has no solution for any m, where A175856(m): a(m) = m for m = noncomposites, a(m) = previous term - 1 for m = composites. 7
8, 9, 14, 15, 24, 25, 32, 33, 38, 39, 54, 55, 62, 63, 74, 75, 90, 91, 92, 93, 98, 99, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 140, 141, 142, 143, 144, 145, 158, 159, 182, 183, 184, 185, 186, 187, 212, 213 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Absent positive integers (pairs of consecutive numbers) in sequence A175856(n).

Complement of A175857(n).

A175860(a(n)) = 0, A175861(a(n)) = 1, A175862(a(n)) = 0.

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..22312

FORMULA

a(2k) = a(2k-1) + 1 for k >= 1.

CROSSREFS

Cf. A175856, A175857, A175858, A175860, A175861, A175862.

Sequence in context: A068780 A174041 A096784 * A059869 A213016 A105833

Adjacent sequences:  A175856 A175857 A175858 * A175860 A175861 A175862

KEYWORD

nonn

AUTHOR

Jaroslav Krizek, Sep 29 2010

STATUS

approved

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Last modified December 11 03:29 EST 2018. Contains 318049 sequences. (Running on oeis4.)