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A093864
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Consider the least k such that prime(k) > n*composite(k). Sequence gives prime(k).
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1
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11, 53, 173, 521, 1523, 4327, 11579, 31469, 85411, 229547, 614477, 1640461, 4393369, 11806297, 31656553, 84979847, 228346229, 614582509, 1654328267, 4457160931, 12016414601, 32419200013, 87508870037, 236325429049, 638490906857, 1725782162981, 4666340800001
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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a(2) = 53 as 53 > 2*26 where 53 and 26 are respectively the 16th prime and composite numbers.
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PROG
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(PARI) nextcomposite(k)=if(k<3, 4, if(isprime(k), k+1, k));
(PARI) p=2; q=4; for(n=1, 19, while(p<=n*q, p=nextprime(p+1); q=nextcomposite(q+1)); print1(p, ", "));
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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