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%I #22 Sep 08 2022 08:45:06
%S 211,421,631,1051,1471,2311,2521,2731,3361,3571,4201,4621,4831,5881,
%T 6091,6301,7351,7561,8191,8821,9241,9661,9871,10501,10711,11131,11551,
%U 11971,12391,12601,13441,14071,14281,15121,15331,15541,16381,17011
%N Primes of the form 210n + 1.
%e 211 = 210*1 + 1 is prime; 1471 = 210*7 + 1 is prime.
%t 210*Flatten[Position[PrimeQ[210Range[100]+1], True]]+1
%t Select[1+210Range[100],PrimeQ] (* _Ray Chandler_, Apr 29 2010 *)
%o (Magma) [ a: n in [0..400] | IsPrime(a) where a is 210*n+1] // _Vincenzo Librandi_, Aug 08 2010
%o (PARI) select(x->((x % 210)==1), primes(3000)) \\ _Michel Marcus_, Jan 14 2018
%Y Subsequence of A142076, A124826, and A132230.
%Y Cf. A073085.
%K easy,nonn
%O 1,1
%A _Zak Seidov_ Aug 24 2002
%E Extended by _Ray Chandler_, Apr 29 2010