A088807 Number of prime factors of p^p - 1 where p is prime.

1, 2, 3, 4, 4, 5, 4, 3, 6, 9, 4, 9, 7, 6, 5, 7, 5, 8, 9, 7, 15, 8, 6, 10, 12, 13

Offset

2,2

Links

Table of n, a(n) for n=2..27.

Mathematica

PrimeNu/@Table[p^p-1, {p, Prime[Range[30]]}] (* The program takes a long time to run. *) (* Harvey P. Dale, Sep 05 2020 *)

Prog

(PARI) omegaptop(n, m) = { sr=0; forprime(x=2, n, y=omega(x^x-m); print1(y", "); sr += 1.0/y; ); print(); }
(Python)
from sympy import factorint, prime
def a(n): p = prime(n); return len(factorint(p**p-1).values())
print([a(n) for n in range(1, 12)]) # Michael S. Branicky, May 27 2022

Crossrefs

Cf. A088730.

Sequence in context: A303998 A319712 A319715 * A036371 A036370 A005208

Adjacent sequences: A088804 A088805 A088806 * A088808 A088809 A088810

Keyword

nonn

Author

Cino Hilliard, Nov 23 2003

Extensions

More terms from Ray Chandler, Feb 21 2004

Status

approved