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A176586 Primes of the form : n^3 + Largest square + Smallest square, (Largest square <= n^3, Smallest square >= n^3). 1
3, 222601, 2824933, 3573761, 4215749, 5183821, 6001997, 6592613, 7886597, 8592401, 9725393, 10127813, 10531813, 12751093, 13720661, 15263009, 18087529, 30232597, 52730113, 68727469, 79395353, 109787269, 139967461, 162040453 (list; graph; refs; listen; history; text; internal format)
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
Sequence in context: A003544 A250495 A317168 * A339776 A033982 A326618
KEYWORD
nonn
AUTHOR
STATUS
approved

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Last modified June 22 15:32 EDT 2024. Contains 373587 sequences. (Running on oeis4.)