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A140555 Primes p such that p + 6 is not a prime. 6
2, 3, 19, 29, 43, 59, 71, 79, 89, 109, 113, 127, 137, 139, 149, 163, 179, 181, 197, 199, 211, 229, 239, 241, 269, 281, 283, 293, 313, 317, 337, 349, 359, 379, 389, 397, 401, 409, 419, 421, 431, 439, 449, 463, 467, 479, 487, 491, 499, 509, 521, 523, 547, 569 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Note that if Goldbach's Conjecture (2n = p1 + p2 for all n>=2) is false and K is the smallest value of n for which it fails, then for 2(K-3) = p3 + p4, the primes p3 and p4 must be taken from this list. See also A067775. - Keith Backman, Apr 05 2012

LINKS

Zak Seidov, Table of n, a(n) for n = 1..10000

FORMULA

A000040 SET MINUS A023201. - R. J. Mathar, Aug 09 2008

MATHEMATICA

Select[Prime[Range[200]], !PrimeQ[#+6]&] (* Harvey P. Dale, Dec 21 2016 *)

PROG

(PARI) forprime(p=2, 600, if(!isprime(p+6), print1(p, ", "))) \\ Klaus Brockhaus, Aug 12 2008

CROSSREFS

Cf. A000040, A023201, A067775.

Sequence in context: A195416 A215383 A215387 * A196446 A265799 A058912

Adjacent sequences:  A140552 A140553 A140554 * A140556 A140557 A140558

KEYWORD

nonn

AUTHOR

Juri-Stepan Gerasimov, Jul 03 2008

EXTENSIONS

Corrected by R. J. Mathar and Klaus Brockhaus, Aug 12 2008

STATUS

approved

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Last modified November 20 14:54 EST 2019. Contains 329337 sequences. (Running on oeis4.)