A239388 Values of n such that n^2 + d^2 is prime for a record first value of d.

1, 3, 8, 9, 12, 23, 30, 48, 63, 114, 141, 408, 651, 1173, 2697, 12639, 30963, 53343, 159537, 283209, 289131, 335511, 601398, 1832421, 2594214, 3533079, 4013361, 15717618, 17449677, 57532827, 186891843, 226385511, 231177657, 242117967

Offset: 1

Author

T. D. Noe, Mar 18 2014

Keywords

• nonn
• more

Comments

See A239389 for the corresponding values of d.

Crossrefs

Cf. A069003 (least number d such that n^2 + d^2 is prime).

Programs

Mathematica

leastK[n_] := Module[{k = 1}, While[! PrimeQ[n^2 + k^2], k++]; k]; nn = 10000; t = {}; kMax = 0; Do[k = leastK[n]; If[k > kMax, kMax = k; AppendTo[t, {n, k}]], {n, nn}]; Transpose[t][[1]]

Extensions

a(24)-a(31) from Giovanni Resta, Mar 18 2014

a(32)-a(34) from Emmanuel Vantieghem, Jan 13 2017