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A085555 Primes p of the form x^2+4, such that either p-2 or p+2 is prime. 1
5, 13, 29, 229, 1093, 1229, 2029, 3253, 4229, 13693, 21613, 59053, 65029, 91813, 140629, 178933, 199813, 205213, 227533, 328333, 366029, 567013, 700573, 804613, 815413, 819029, 1071229, 1155629, 1311029, 1575029, 2241013, 3629029, 3822029 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

MAPLE

select(t -> isprime(t) and (isprime(t+2) or isprime(t-2)), [seq(x^2+4, x=1..10^4, 2)]); # Robert Israel, May 14 2018

MATHEMATICA

okQ[n_]:=PrimeQ[n]&&(PrimeQ[n-2]||PrimeQ[n+2]); Select[Range[ 2000]^2+4, okQ] (* Harvey P. Dale, Jul 14 2011 *)

CROSSREFS

Sequence in context: A146420 A147492 A182069 * A224888 A256314 A002768

Adjacent sequences:  A085552 A085553 A085554 * A085556 A085557 A085558

KEYWORD

easy,nonn

AUTHOR

Cino Hilliard, Jul 04 2003

EXTENSIONS

Edited by Don Reble, May 03 2006

STATUS

approved

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Last modified July 29 17:41 EDT 2021. Contains 346346 sequences. (Running on oeis4.)