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A226986
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Primes p such that both prevprime(p^2) - 2 and nextprime(p^2) + 2 are also primes.
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1
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3, 251, 409, 647, 1031, 1669, 6469, 6679, 12043, 18313, 18517, 31583, 31643, 32957, 33479, 33529, 37783, 39733, 40163, 44071, 58441, 67189, 68279, 83009, 83117, 83423, 87671, 90481, 96001, 98479, 112951, 120011, 130211, 149939, 152297, 155663, 156227, 158293
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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Select[Prime[Range[15000]], AllTrue[{NextPrime[#^2, -1]-2, NextPrime[ #^2]+2}, PrimeQ]&] (* Harvey P. Dale, Jun 12 2022 *)
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PROG
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(PARI) is(n)=isprime(precprime(n^2)-2) && isprime(nextprime(n^2)+2) && isprime(n) \\ Charles R Greathouse IV, Jun 25 2013
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CROSSREFS
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KEYWORD
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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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