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A097452
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Primes p of the form p = prime(k) + composite(k) for some k.
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0
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3, 7, 11, 23, 29, 71, 101, 139, 151, 157, 199, 229, 239, 251, 263, 311, 347, 367, 401, 443, 479, 547, 601, 653, 673, 691, 709, 853, 977, 991, 1013, 1051, 1087, 1181, 1237, 1291, 1327, 1451, 1487, 1579, 1637, 1693, 1721, 1753, 1777, 1861, 1877, 1913, 1951
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OFFSET
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1,1
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COMMENTS
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Are there infinitely many such primes?
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LINKS
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Table of n, a(n) for n=1..49.
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EXAMPLE
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The 6-th prime is 13, the 6-th composite is 10. 13+10=23 the 4th entry in the table.
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PROG
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(PARI) primepcomp(n) = { for(x=1, n, y=prime(x)+ composite(x); if(isprime(y), print1(y", ")) ) } \ the n-th composite composite(n) = { local(c, x); c=1; x=0; while(c <= n, x++; if(!isprime(x), c++); ); return(x) }
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CROSSREFS
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Sequence in context: A187106 A111668 A112038 * A086505 A154427 A095102
Adjacent sequences: A097449 A097450 A097451 * A097453 A097454 A097455
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KEYWORD
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nonn
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AUTHOR
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Cino Hilliard (hillcino368(AT)gmail.com), Aug 23 2004
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STATUS
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approved
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