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.

A384369 Numbers k such that Omega(k)^Omega(k) == Omega(k) (mod k) where Omega = A001222.

Original entry on oeis.org

1, 2, 3, 5, 7, 8, 11, 12, 13, 17, 19, 23, 29, 31, 36, 37, 41, 43, 47, 48, 53, 59, 61, 67, 71, 73, 79, 80, 83, 84, 89, 97, 101, 103, 107, 109, 113, 120, 126, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 208, 211, 223, 227, 229, 233, 239, 241
Offset: 1

Views

Author

Juri-Stepan Gerasimov, May 30 2025

Keywords

Examples

			8 is a term because Omega(8)^Omega(8) = 3^3 = 27 == 3 (mod 8).
		

Crossrefs

Supersequence of primes A000040.
Cf. A001222.

Programs

  • Magma
    [k: k in [1..250] | (k eq 1 select 0 else &+[p[2]: p in Factorization(k)])^(k eq 1 select 0 else &+[p[2]: p in Factorization(k)]) mod k eq (k eq 1 select 0 else &+[p[2]: p in Factorization(k)])];
  • Mathematica
    {1}~Join~Select[Range[2,241],Mod[PrimeOmega[#]^PrimeOmega[#],#]==PrimeOmega[#]&] (* James C. McMahon, Jun 04 2025 *)