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A038133
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From a subtractive Goldbach conjecture: odd primes that are not cluster primes.
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5
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97, 127, 149, 191, 211, 223, 227, 229, 251, 257, 263, 269, 293, 307, 331, 337, 347, 349, 367, 373, 379, 383, 397, 409, 419, 431, 457, 479, 487, 499, 521, 541, 547, 557, 563, 569, 587, 593, 599, 631, 641, 673, 691, 701, 709, 719, 727, 733, 739, 743, 751
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| Erdos asks if there are infinitely many primes p such that every even number <= p-3 can be expressed as the difference between two primes each <= p. Sequence gives primes not having this property.
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REFERENCES
| R. Blecksmith et al., Cluster primes, Amer. Math. Monthly, 106 (1999), 43-48.
R. K. Guy, Unsolved Problems In Number Theory, section C1.
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LINKS
| T. D. Noe, Table of n, a(n) for n=1..10000
Eric Weisstein's World of Mathematics, Link to a section of The World of Mathematics.
Index entries for sequences related to Goldbach conjecture
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MATHEMATICA
| m=1000; lst={}; n=PrimePi[m]-1; p=Table[Prime[i+1], {i, n}]; d=Table[0, {m/2}]; For[i=2, i<=n, i++, For[j=1, j<i, j++, diff=p[[i]]-p[[j]]; d[[diff/2]]++ ]; c=Count[Take[d, (p[[i]]-3)/2], 0]; If[c>0, AppendTo[lst, p[[i]]]]]; lst
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CROSSREFS
| Cf. A038134, A039506, A039507, A072325.
Sequence in context: A078494 A139980 A140830 * A144325 A161367 A073076
Adjacent sequences: A038130 A038131 A038132 * A038134 A038135 A038136
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KEYWORD
| nonn,easy,nice
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AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com).
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EXTENSIONS
| More terms from Christian G. Bower (bowerc(AT)usa.net), Feb 15 1999.
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