A176586 Primes of the form : n^3 + Largest square + Smallest square, (Largest square <= n^3, Smallest square >= n^3).
3, 222601, 2824933, 3573761, 4215749, 5183821, 6001997, 6592613, 7886597, 8592401, 9725393, 10127813, 10531813, 12751093, 13720661, 15263009, 18087529, 30232597, 52730113, 68727469, 79395353, 109787269, 139967461, 162040453
Offset: 1
Keywords
Links
- Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
Programs
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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 *) -
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