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%I A038133
%S A038133 97,127,149,191,211,223,227,229,251,257,263,269,293,307,331,337,347,
%T A038133 349,367,373,379,383,397,409,419,431,457,479,487,499,521,541,547,557,
%U A038133 563,569,587,593,599,631,641,673,691,701,709,719,727,733,739,743,751
%N A038133 From a subtractive Goldbach conjecture: odd primes that are not cluster 
               primes.
%C A038133 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.
%D A038133 R. Blecksmith et al., Cluster primes, Amer. Math. Monthly, 106 (1999), 
               43-48.
%D A038133 R. K. Guy, Unsolved Problems In Number Theory, section C1.
%H A038133 T. D. Noe, <a href="b038133.txt">Table of n, a(n) for n=1..10000</a>
%H A038133 Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/
               ClusterPrime.html">Link to a section of The World of Mathematics.</
               a>
%H A038133 <a href="Sindx_Go.html#Goldbach">Index entries for sequences related 
               to Goldbach conjecture</a>
%t A038133 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
%Y A038133 Cf. A038134, A039506, A039507, A072325.
%Y A038133 Sequence in context: A078494 A139980 A140830 this_sequence A144325 A161367 
               A073076
%Y A038133 Adjacent sequences: A038130 A038131 A038132 this_sequence A038134 A038135 
               A038136
%K A038133 nonn,easy,nice
%O A038133 1,1
%A A038133 N. J. A. Sloane (njas(AT)research.att.com).
%E A038133 More terms from Christian G. Bower (bowerc(AT)usa.net), Feb 15 1999.

    
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Last modified November 27 22:38 EST 2009. Contains 167602 sequences.


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