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A075750
210*n -/+ 11 are primes.
1
2, 3, 5, 7, 9, 10, 13, 17, 26, 29, 34, 45, 48, 54, 57, 59, 60, 61, 63, 75, 82, 89, 108, 112, 113, 123, 133, 136, 139, 140, 146, 147, 148, 150, 151, 153, 156, 166, 167, 172, 173, 174, 175, 177, 184, 185, 195, 208, 210, 215, 227, 245, 250, 265, 266, 269, 278, 279
OFFSET
1,1
LINKS
EXAMPLE
n=2: 210*2-11=409 and 210*2+11=431 are primes.
MATHEMATICA
Select[Range[1, 300], PrimeQ[210 # - 11]&&PrimeQ[210 # + 11] &] (* Vincenzo Librandi, Oct 05 2013 *)
PROG
(PARI) isok(n) = isprime(210*n+11) && isprime(210*n-11); \\ Michel Marcus, Oct 03 2013
(Magma) [n: n in [1..350] | IsPrime(210*n-11) and IsPrime(210*n+11)]; // Vincenzo Librandi, Oct 05 2013
CROSSREFS
Sequence in context: A133677 A362403 A379155 * A331232 A219050 A036049
KEYWORD
easy,nonn
AUTHOR
Zak Seidov, Oct 08 2002
STATUS
approved