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A247269
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Primes p such that p + m^2 is prime for all m in {2,4,6,8,10,12,14,16,18}.
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4
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163, 409333, 1483087, 1867783, 222640867, 258001837, 371305267, 748576753, 828497443, 1235054137, 2059599067, 5767711867, 5929920613, 8965599883, 9055004953, 9170160343, 9655686727, 9670115977, 9671300983, 10646399437, 12253792783, 12627473917, 19635778453
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OFFSET
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1,1
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COMMENTS
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All terms are == 1 mod 6, and == {7, 13} mod 30.
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LINKS
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PROG
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(PARI)
forprime(p=1, 10^12, c=0; for(i=1, 9, if(ispseudoprime(p+(2*i)^2), c++); if(!ispseudoprime(p+(2*i)^2), break)); if(c==9, print1(p, ", "))) \\ Derek Orr, Sep 11 2014
(PARI) is(n)=my(t=n%5); if(t!=2 && t!=3, return(0)); forstep(i=4, 18, 2, if(!isprime(n+i^2), return(0))); isprime(n) && isprime(n+4)
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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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