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%I #29 Dec 27 2019 05:52:44
%S 3,7,7,11,13,17,19,23,37,41,43,47,67,71,79,83,97,101,103,107,109,113,
%T 127,131,163,167,193,197,223,227,229,233,277,281,307,311,313,317,349,
%U 353,379,383,397,401,439,443,457,461,463,467,487,491,499,503,613,617,643
%N List of pairs of primes (p, q) with q - p = 4.
%C The two primes p and p+4 are not necessarily consecutive primes (for that, see A111980).
%C The pairs are listed in order, sorted by their smallest member. - _N. J. A. Sloane_, Dec 27 2019
%H Seiichi Manyama, <a href="/A094343/b094343.txt">Table of n, a(n) for n = 1..10000</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/CousinPrimes.html">Cousin Primes</a>
%F a(2*n-1)=A023200(n). a(2*n)=A046132(n).
%e The pairs are (3,7), (7,11), (13,17), etc.
%t Flatten[{#,#+4}&/@Select[Prime[Range[200]],PrimeQ[#+4]&]] (* _Harvey P. Dale_, Apr 13 2011 *)
%o (PARI) isok(n) = (isprime(n) && isprime(n+4)) || (isprime(n-4) && isprime(n)); \\ _Michel Marcus_, Aug 26 2013
%Y Almost identical to A111980.
%Y Union of A023200 and A046132.
%Y Cf. twin primes (A001097).
%Y See also A000040, A111981, A001097.
%Y For a gap of 6 (which initially is very common) see A140546.
%K easy,nonn
%O 1,1
%A _Gerard Schildberger_, Jun 04 2004
%E Description was corrupted up during editing; correct description restored Aug 21 2005.
%E a(3) = 7 added by _Vincenzo Librandi_, May 06 2016
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