OFFSET
1,1
COMMENTS
Starting at a(3) all primes in this sequence are of the form (2*k+1)*(2*k+3)+(2*k+3)*(2*k+5)+(2*k+5)*(2*k+7) = 12*k^2 + 48*k + 53 for some k >= 0. For example a(5) = 5*7 + 7*9 + 9*11 = 197. - J. M. Bergot, Nov 03 2014
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..5000
MATHEMATICA
Select[Table[3n^2 + 5, {n, 0, 700}], PrimeQ]
PROG
(Magma) [a: n in [0..400] | IsPrime(a) where a is 3*n^2+5];
(PARI) select(isprime, vector(100, n, 3*n^2+5)) \\ Charles R Greathouse IV, Nov 05 2014
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Dec 02 2011
STATUS
approved