OFFSET
1,2
COMMENTS
EXAMPLE
If k = 11 then 41 + (k + k^2) / 2 = 107 (prime).
MATHEMATICA
Select[Table[Range[0, 1000]], PrimeQ[41+(#+#^2)/2]&]
PROG
(PARI) is(n)=isprime(n*(n+1)/2+41) \\ Charles R Greathouse IV, Aug 16 2015
(Magma) [k:k in [0..530]| IsPrime(41+(k+k^2) div 2)]; // Marius A. Burtea, Feb 12 2020
CROSSREFS
KEYWORD
nonn
AUTHOR
Zak Seidov, Apr 11 2008
STATUS
approved