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A067774 Primes p such that p+2 is not a prime. 4
2, 7, 13, 19, 23, 31, 37, 43, 47, 53, 61, 67, 73, 79, 83, 89, 97, 103, 109, 113, 127, 131, 139, 151, 157, 163, 167, 173, 181, 193, 199, 211, 223, 229, 233, 241, 251, 257, 263, 271, 277, 283, 293, 307, 313, 317, 331, 337, 349, 353, 359, 367, 373, 379, 383, 389 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

Primes n such that n!*B(n+1) is an integer where B(k) are the Bernoulli numbers.

All primes except for the lower members of twin primes - i.e. remove 3, 5, 11, 17, 29, 41, 59, 71, 101, 107, 137, ... - Gerard Schildberger (gerards(AT)rrt.net), Feb 13 2005

FORMULA

Except for a(1)=2, a(n+1)=A049591(n)

MATHEMATICA

f[n_]:=PrimeQ[n+2]; lst={}; Do[p=Prime[n]; If[ !f[p], AppendTo[lst, p]], {n, 5!}]; lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Oct 17 2009]

CROSSREFS

Cf. A049591.

Complement of A001359 in A000040, A025584, A007510.

Sequence in context: A155547 A007821 A156007 * A063637 A020623 A109346

Adjacent sequences:  A067771 A067772 A067773 * A067775 A067776 A067777

KEYWORD

nonn

AUTHOR

Benoit Cloitre (benoit7848c(AT)orange.fr), Feb 06 2002

EXTENSIONS

Better description from Vladeta Jovovic (vladeta(AT)eunet.rs), Dec 14 2002

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Last modified February 13 18:31 EST 2012. Contains 205535 sequences.