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A079141
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Primes of the form p^2 + 6 where p is prime.
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4
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31, 127, 367, 967, 3727, 6247, 7927, 11887, 17167, 22807, 39607, 72367, 109567, 160807, 185767, 323767, 502687, 737887, 863047, 885487, 942847, 982087, 1079527, 1560007, 1739767, 1852327, 1985287, 2105407, 2343967, 2399407
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OFFSET
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1,1
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COMMENTS
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Sum of reciprocals = 0.0447155381... [4 additional digits from Jon E. Schoenfield, Jan 15 2015]
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LINKS
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MATHEMATICA
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Select[#^2+6&/@Prime[Range[300]], PrimeQ] (* Harvey P. Dale, Nov 16 2012 *)
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PROG
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(PARI) sqppn(n) = {sr=0; forprime(x=3, n, y = x*x+6; if(isprime(y), print1(y" "); sr+=1.0/y; ); ); print(); print(sr); } \\ Primes of the form p^2 + 6 and the sum of the reciprocals.
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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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STATUS
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approved
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