OFFSET
1,1
LINKS
Peter J. C. Moses, Table of n, a(n) for n = 1..10000
EXAMPLE
42 is included because 4*42^2+1, 2*42^2+1, 2*42^2-1 are all prime numbers.
MAPLE
with(numtheory): for n from 1 to 50000 do if isprime(4*n^2+1) and isprime(2*n^2+1) and isprime(2*n^2-1) then printf(`%d, `, n) fi: od:
MATHEMATICA
a={}; Do[If[PrimeQ[4n^2+1] && PrimeQ[2n^2+1] && PrimeQ[2n^2-1], AppendTo[a, n]], {n, 10000}]; a (* Peter J. C. Moses, Apr 02 2013 *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Harvey P. Dale, Jul 12 2000
EXTENSIONS
More terms from James A. Sellers, Jul 13 2000
STATUS
approved