cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A144137 Numbers n such that between n^K and (n+1)^K there are no primes, where K = sqrt(2).

Original entry on oeis.org

4, 24, 29, 33, 40, 43, 56, 59, 84, 117, 122, 128, 132, 139, 145, 156, 162, 163, 183, 190, 203, 230, 253, 257, 286, 297, 303, 306, 315, 319, 336, 371, 403, 420, 433, 447, 456, 467, 479, 537, 543, 563, 592, 595, 599, 624, 699, 746, 755, 767, 774, 782, 805, 814
Offset: 1

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Author

Artur Jasinski, Sep 11 2008

Keywords

Examples

			a(1)=4 because in range 4^sqrt(2) = 7.10299... and (4+1)^sqrt(2) = 9.73852... there are no primes (8 and 9 aren't primes).
		

Crossrefs

Programs

  • Mathematica
    a = {}; k = Sqrt[2]; Do[If[Length[Select[Range[Ceiling[n^k], Floor[(n + 1)^k]], PrimeQ]] == 0, AppendTo[a, n]], {n, 3000}]; a
    Select[Range[850],PrimePi[(#+1)^Sqrt[2]]-PrimePi[#^Sqrt[2]]==0&] (* or *) SequencePosition[PrimePi[Range[850]^Sqrt[2]],{x_,x_}][[All,1]] (* Harvey P. Dale, Jul 31 2021 *)