A176584
Primes of the form p = k^3 + (largest square <= k^3).
Original entry on oeis.org
2, 194057, 601067, 1607173, 3283993, 3630257, 3721363, 4918999, 5255713, 5848307, 6749569, 9999907, 17992913, 20432729, 23393483, 34746203, 44845993, 73843813, 84277273, 107165033, 109735649, 120469409, 125138873, 130898927
Offset: 1
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g:= n -> n + floor(sqrt(n))^2:
select(isprime,map(g,[seq(i^3,i=1..1000)])); # Robert Israel, Jan 10 2024
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r[n_]:=n^3;f[n_]:=r[n]+Floor[Sqrt[r[n]]]^2;Select[Table[f[n],{n,0,6!}],PrimeQ[ # ]&]
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select(isprime, vector(1000, n, n^3+sqrtint(n^3)^2)) \\ Michel Marcus, Jan 10 2024
A176585
Primes of the form n^3+Smallest square, (Smallest square >= n^3).
Original entry on oeis.org
2, 17, 269, 281233, 1770217, 1826609, 2520841, 3907529, 7595017, 8665471, 9828089, 11280377, 12259063, 17235221, 27654961, 54008809, 70583033, 75196799, 85018949, 87240233, 106316057, 111499057, 168061561, 176255669, 201105409
Offset: 1
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r[n_]:=n^3;f[n_]:=r[n]+Ceiling[Sqrt[r[n]]]^2;Select[Table[f[n],{n,0,6!}],PrimeQ[ # ]&]
ssn3[n_]:=n^3+(Ceiling[Sqrt[n^3]])^2; Select[Array[ssn3,500],PrimeQ] (* Harvey P. Dale, Jun 23 2017 *)
A176586
Primes of the form : n^3 + Largest square + Smallest square, (Largest square <= n^3, Smallest square >= n^3).
Original entry on oeis.org
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
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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 *)
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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
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