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A115058
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Primes p such that 3p+2 is not prime.
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4
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2, 11, 31, 41, 47, 53, 61, 67, 71, 73, 101, 107, 109, 113, 131, 137, 151, 157, 179, 181, 191, 193, 211, 223, 229, 241, 251, 263, 271, 277, 281, 283, 307, 311, 331, 347, 359, 373, 379, 389, 401, 421, 431, 443, 449, 461, 463, 467, 487, 491, 509, 521, 541, 547
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OFFSET
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1,1
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COMMENTS
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Primes p that are also the largest prime factor of p(p^2-1)(3p+2)/24.
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REFERENCES
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Number Theory, George E. Andrews 1971, Dover Publications New York, p 4.
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LINKS
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EXAMPLE
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p=11, p(p^2-1)(3p+2)/24 = 1925 = 5*5*7*11.
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MATHEMATICA
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PROG
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(Magma) [p: p in PrimesUpTo(600) | not IsPrime(3*p + 2)]; // Vincenzo Librandi, Apr 17 2013
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CROSSREFS
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KEYWORD
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easy,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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