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A049489
Primes p such that p + 32 is also prime.
10
5, 11, 29, 41, 47, 71, 107, 131, 149, 167, 179, 191, 197, 239, 251, 281, 317, 347, 389, 401, 431, 467, 491, 509, 569, 587, 599, 641, 659, 677, 701, 719, 797, 821, 827, 887, 977, 1019, 1031, 1061, 1091, 1097, 1181, 1217, 1259, 1289, 1367, 1427, 1439, 1451
OFFSET
1,1
LINKS
EXAMPLE
29 and 29 + 32 = 61 are both prime.
MAPLE
Primes:= select(isprime, {seq(i, i=3..10000, 2)}):
sort(convert(Primes intersect map(`-`, Primes, 32), list)); # Robert Israel, Dec 20 2015
MATHEMATICA
Select[Range[2000], PrimeQ[#] && PrimeQ[# + 32] &] (* Vincenzo Librandi, Apr 22 2015 *)
Select[Prime[Range[300]], PrimeQ[#+32]&] (* Harvey P. Dale, Oct 14 2017 *)
PROG
(PARI) isok(n) = isprime(n) && isprime(n+32); \\ Michel Marcus, Dec 31 2013
(Magma) [[p: p in PrimesUpTo(2000) | IsPrime(p+32)]; // Vincenzo Librandi, Apr 22 2015
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
EXTENSIONS
Name improved by Bruno Berselli, Apr 22 2015
STATUS
approved