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A023200
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Primes p such that p + 4 is also prime.
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76
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3, 7, 13, 19, 37, 43, 67, 79, 97, 103, 109, 127, 163, 193, 223, 229, 277, 307, 313, 349, 379, 397, 439, 457, 463, 487, 499, 613, 643, 673, 739, 757, 769, 823, 853, 859, 877, 883, 907, 937, 967, 1009, 1087, 1093, 1213, 1279, 1297, 1303, 1423, 1429, 1447, 1483
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| Smaller member p of cousin prime pairs (p, p+4).
A015913 contains the composite number 305635357, so is different from the present sequence and A029710 (305635357 is the only composite member of A015913 < 10^9) - Jud McCranie (JudMcCranie(AT)ugaalum.uga.edu), Jan 07, 2001.
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LINKS
| T. D. Noe, Table of n, a(n) for n=1..10000
A. Granville and G. Martin, Prime number races
Eric Weisstein's World of Mathematics, Cousin Primes
Eric Weisstein's World of Mathematics, Twin Primes
Index entries for primes, gaps between
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FORMULA
| a(n) = A046132(n) - 4 = A087679(n) - 2.
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MAPLE
| A023200 := proc(n) option remember; if n = 1 then 3; else p := nextprime(procname(n-1)) ; while not isprime(p+4) do p := nextprime(p) ; end do: p ; end if; end proc: # R. J. Mathar, Sep 03 2011
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MATHEMATICA
| Select[Range[10^2], PrimeQ[ # ]&&PrimeQ[ #+4] &] (from Vladimir Orlovsky (4vladimir(AT)gmail.com), Apr 29 2008)
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CROSSREFS
| Essentially the same as A029710.
Cf. A000010, A003557, A007947, A046132, A098429.
Sequence in context: A048977 A154650 A015913 * A046136 A098044 A134765
Adjacent sequences: A023197 A023198 A023199 * A023201 A023202 A023203
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KEYWORD
| nonn
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AUTHOR
| David W. Wilson (davidwwilson(AT)comcast.net)
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EXTENSIONS
| Definition revised by N. J. A. Sloane, Mar 05 2010
Definition modified by Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Aug 02 2009
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