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A226986 Primes p such that both prevprime(p^2) - 2 and nextprime(p^2) + 2 are also primes. 1
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

PROG

(PARI) is(n)=isprime(precprime(n^2)-2) && isprime(nextprime(n^2)+2) && isprime(n) \\ Charles R Greathouse IV, Jun 25 2013

CROSSREFS

Sequence in context: A157777 A318065 A124875 * A158351 A025418 A075901

Adjacent sequences:  A226983 A226984 A226985 * A226987 A226988 A226989

KEYWORD

nonn

AUTHOR

Juri-Stepan Gerasimov, Jun 25 2013

EXTENSIONS

a(3)-a(34) from by Giovanni Resta, Jun 13 2013

a(10) inserted by Charles R Greathouse IV, Jun 25 2013

STATUS

approved

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Last modified March 22 17:25 EDT 2019. Contains 321422 sequences. (Running on oeis4.)