OFFSET
1,1
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
MATHEMATICA
r[n_]:=n^3; f[n_]:=r[n]+Floor[Sqrt[r[n]]]^2+Ceiling[Sqrt[r[n]]]^2; Select[Table[f[n], {n, 0, 7!}], PrimeQ[ # ]&]
lsss[n_]:=Module[{c=n^3}, c+Floor[Sqrt[c]]^2+Ceiling[Sqrt[c]]^2]; Select[Array[ lsss, 1000], PrimeQ] (* Harvey P. Dale, Feb 22 2023 *)
PROG
(PARI) print1(3); for(n=2, 1e3, t=sqrtint(n^3); if(isprime(t=n^3+t^2+ (t+1)^2) && !issquare(n), print1(", "t))) \\ Charles R Greathouse IV, Apr 15 2012
CROSSREFS
KEYWORD
nonn
AUTHOR
Vladimir Joseph Stephan Orlovsky, Apr 21 2010
STATUS
approved