OFFSET
1,1
COMMENTS
Conjecture: 2^a(n)-1 is not prime; in other words, these primes are included in A054723.
2*a(n)+579 is a square. - Vincenzo Librandi, Mar 04 2013
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..3000
MATHEMATICA
Select[Table[2 n^2 + 50 n + 23, {n, 0, 500}], PrimeQ]
PROG
(Magma) [a: n in [0..200] | IsPrime(a) where a is 2*n^2 + 50*n + 23];
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Oct 09 2012
STATUS
approved