OFFSET
1,1
EXAMPLE
2^3 + 2^2 = 12 -+ 1 = 11 and 13 (both prime).
MATHEMATICA
lst={}; Do[k=n^3+n^2; If[PrimeQ[k-1]&&PrimeQ[k+1], AppendTo[lst, n]], {n, 8!}]; lst
Select[Range[3000], PrimeQ[#^3 + #^2 - 1] && PrimeQ[#^3 + #^2 + 1] &] (* Vincenzo Librandi, Dec 26 2015 *)
PROG
(Magma) [n: n in [1..5*10^3] |IsPrime(n^3+n^2-1) and IsPrime(n^3+n^2+1)]; // Vincenzo Librandi, Dec 26 2015
(PARI) isok(n) = isprime(n^3+n^2+1) && isprime(n^3+n^2-1); \\ Michel Marcus, Dec 27 2015
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Vladimir Joseph Stephan Orlovsky, Jan 14 2009
STATUS
approved