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A338175
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Primes p such that (p^2+6)/5 is prime.
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1
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2, 3, 7, 17, 23, 47, 53, 157, 173, 193, 233, 347, 353, 373, 383, 443, 457, 577, 823, 857, 907, 1117, 1153, 1193, 1223, 1277, 1447, 1453, 1523, 1697, 1733, 1823, 1873, 2027, 2153, 2203, 2293, 2333, 2357, 2467, 2557, 2657, 2683, 2707, 2777, 2797, 2803, 2903, 3217, 3253, 3323, 3407, 3433, 3643, 3673
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OFFSET
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1,1
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COMMENTS
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All terms end in 2, 3 or 7.
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LINKS
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EXAMPLE
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a(3)=7 is a member because 7 is prime and (7^2+6)/5 = 11 is prime.
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MAPLE
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select(p -> isprime(p) and isprime((p^2+6)/5), [2, seq(seq(10*i+j, j=[3, 7]), i=0..1000)]);
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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