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A173295 Primes of the form n^2+n+1 or n^2+n+9. 0

%I #5 Aug 28 2012 17:41:39

%S 3,7,11,13,29,31,43,73,157,191,211,241,281,307,389,421,463,601,659,

%T 757,821,1123,1483,1723,1901,2459,2551,2971,3089,3307,3541,3907,4423,

%U 4831,5113,5701,5861,6007,6163,6329,6481,7841,8011,8191,9901,10303,11131

%N Primes of the form n^2+n+1 or n^2+n+9.

%e a(1)=3 because 1^2+1+1=3 is prime, a(3)=11 because 1^2+1+9=11 is prime.

%t Union[Select[Flatten[Table[n^2+n+{1,9},{n,200}]],PrimeQ]] (* _Harvey P. Dale_, Aug 28 2012 *)

%Y Cf. A002378, A173288.

%K nonn

%O 1,1

%A _Juri-Stepan Gerasimov_, Feb 15 2010

%E Added 3, removed 133, replaced 607 by 601 - _R. J. Mathar_, Feb 24 2010

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