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A167692 The even nonisolated nonprimes. 3
0, 8, 10, 14, 16, 20, 22, 24, 26, 28, 32, 34, 36, 38, 40, 44, 46, 48, 50, 52, 54, 56, 58, 62, 64, 66, 68, 70, 74, 76, 78, 80, 82, 84, 86, 88, 90, 92, 94, 96, 98, 100, 104, 106, 110, 112, 114, 116, 118, 120, 122, 124, 126, 128, 130, 132, 134, 136, 140, 142, 144, 146, 148 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Zero together with A100319, the even numbers n such that at least one of n-1 and n+1 is composite.

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..1000

MATHEMATICA

Select[Range[0, 100], Mod[#, 2] == 0 && !PrimeQ[#] && (! PrimeQ[# - 1] || !PrimeQ[# + 1]) &] (* G. C. Greubel, Jul 07 2016 *)

PROG

(PARI) isA167692(n) = (n%2==0)&&!isprime(n)&&(!isprime(n-1)||!isprime(n+1)) \\ Michael B. Porter, Feb 02 2010

CROSSREFS

Cf. A100319, A164276.

Sequence in context: A030490 A076639 A100319 * A171689 A163628 A060864

Adjacent sequences:  A167689 A167690 A167691 * A167693 A167694 A167695

KEYWORD

nonn,easy,less

AUTHOR

Juri-Stepan Gerasimov, Nov 09 2009

EXTENSIONS

Edited by Charles R Greathouse IV, Mar 22 2010

STATUS

approved

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Last modified March 23 05:36 EDT 2019. Contains 321422 sequences. (Running on oeis4.)