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A094343
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List of pairs of primes (p, q) with q - p = 4.
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10
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3, 7, 7, 11, 13, 17, 19, 23, 37, 41, 43, 47, 67, 71, 79, 83, 97, 101, 103, 107, 109, 113, 127, 131, 163, 167, 193, 197, 223, 227, 229, 233, 277, 281, 307, 311, 313, 317, 349, 353, 379, 383, 397, 401, 439, 443, 457, 461, 463, 467, 487, 491, 499, 503, 613, 617, 643
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OFFSET
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1,1
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COMMENTS
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The two primes p and p+4 are not necessarily consecutive primes (for that, see A111980).
The pairs are listed in order, sorted by their smallest member. - N. J. A. Sloane, Dec 27 2019
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LINKS
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FORMULA
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EXAMPLE
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The pairs are (3,7), (7,11), (13,17), etc.
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MATHEMATICA
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Flatten[{#, #+4}&/@Select[Prime[Range[200]], PrimeQ[#+4]&]] (* Harvey P. Dale, Apr 13 2011 *)
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PROG
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(PARI) isok(n) = (isprime(n) && isprime(n+4)) || (isprime(n-4) && isprime(n)); \\ Michel Marcus, Aug 26 2013
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CROSSREFS
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For a gap of 6 (which initially is very common) see A140546.
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KEYWORD
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easy,nonn
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AUTHOR
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EXTENSIONS
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Description was corrupted up during editing; correct description restored Aug 21 2005.
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STATUS
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approved
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