OFFSET
2,2
COMMENTS
Old name was: Numbers n such that sqrt(4*n+9) is prime.
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 2..1000
FORMULA
4*a(n)+9 = A001248(n).
a(n) = A166011(n)/2. - Michel Marcus, Apr 22 2016
MATHEMATICA
Select[Range[0, 10000], PrimeQ[Sqrt[4 # + 9]]&]
PROG
(Magma) [(p^2-9)/4: p in PrimesInInterval(3, 200)];
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Apr 05 2013
STATUS
approved