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.

A103335 Numbers whose smallest primitive root (A046145) is not prime.

Original entry on oeis.org

1, 2, 41, 109, 151, 229, 251, 271, 313, 337, 362, 367, 409, 439, 542, 626, 674, 733, 761, 818, 878, 971, 991, 1021, 1031, 1069, 1289, 1297, 1303, 1429, 1471, 1489, 1681, 1759, 1783, 1789, 1811, 1871, 1873, 1879, 2062, 2137, 2342, 2411, 2441, 2551, 2594
Offset: 1

Views

Author

Harry J. Smith, Jan 31 2005

Keywords

Crossrefs

Programs

  • Maple
    filter:= proc(n)
      local r;
      r:= numtheory:-primroot(n);
      r <> FAIL and not isprime(r)
    end proc:
    filter(1):= true:
    select(filter, [$1..3000]); Robert Israel, Sep 08 2020
  • Mathematica
    L = {}; Do[ If[!PrimeQ[ Min[ Select[ Range[n], CoprimeQ[#, n] && MultiplicativeOrder[#, n] == CarmichaelLambda[n] &]]],
    L = Append[L, n]], {n, 1, 3000}]; L (* Jonathan Sondow, May 17 2017 *)

Extensions

Offset changed by Robert Israel, Sep 08 2020