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A073102
Primes of the form 210n + 1.
21
211, 421, 631, 1051, 1471, 2311, 2521, 2731, 3361, 3571, 4201, 4621, 4831, 5881, 6091, 6301, 7351, 7561, 8191, 8821, 9241, 9661, 9871, 10501, 10711, 11131, 11551, 11971, 12391, 12601, 13441, 14071, 14281, 15121, 15331, 15541, 16381, 17011
OFFSET
1,1
EXAMPLE
211 = 210*1 + 1 is prime; 1471 = 210*7 + 1 is prime.
MATHEMATICA
210*Flatten[Position[PrimeQ[210Range[100]+1], True]]+1
Select[1+210Range[100], PrimeQ] (* Ray Chandler, Apr 29 2010 *)
PROG
(Magma) [ a: n in [0..400] | IsPrime(a) where a is 210*n+1] // Vincenzo Librandi, Aug 08 2010
(PARI) select(x->((x % 210)==1), primes(3000)) \\ Michel Marcus, Jan 14 2018
CROSSREFS
Subsequence of A142076, A124826, and A132230.
Cf. A073085.
Sequence in context: A147156 A140535 A258332 * A076167 A217620 A289993
KEYWORD
easy,nonn
AUTHOR
Zak Seidov Aug 24 2002
EXTENSIONS
Extended by Ray Chandler, Apr 29 2010
STATUS
approved