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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A067774 Primes p such that p+2 is not a prime.

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%I A067774 #18 Sep 08 2022 08:45:05
%S A067774 2,7,13,19,23,31,37,43,47,53,61,67,73,79,83,89,97,103,109,113,127,131,
%T A067774 139,151,157,163,167,173,181,193,199,211,223,229,233,241,251,257,263,
%U A067774 271,277,283,293,307,313,317,331,337,349,353,359,367,373,379,383,389
%N A067774 Primes p such that p+2 is not a prime.
%C A067774 Primes n such that n!*B(n+1) is an integer where B(k) are the Bernoulli numbers.
%C A067774 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_, Feb 13 2005
%H A067774 T. D. Noe, <a href="/A067774/b067774.txt">Table of n, a(n) for n = 1..1000</a>
%F A067774 Except for a(1)=2, a(n+1)=A049591(n).
%F A067774 a(n) ~ n log n. - _Charles R Greathouse IV_, Jul 01 2013
%t A067774 f[n_]:=PrimeQ[n+2]; lst={}; Do[p=Prime[n]; If[ !f[p], AppendTo[lst,p]], {n,5!}]; lst (* _Vladimir Joseph Stephan Orlovsky_, Oct 17 2009 *)
%o A067774 (Magma) [p: p in PrimesUpTo(400) | NextPrime(p)-p ne 2]; // _Bruno Berselli_, Apr 09 2013
%o A067774 (PARI) is(n)=isprime(n)&&!isprime(n+2) \\ _Charles R Greathouse IV_, Jul 01 2013
%Y A067774 Cf. A049591.
%Y A067774 Complement of A001359 in A000040, A025584, A007510.
%K A067774 nonn,easy
%O A067774 1,1
%A A067774 _Benoit Cloitre_, Feb 06 2002
%E A067774 Better description from _Vladeta Jovovic_, Dec 14 2002