A088816 Numbers of the form p^p - 2 where p is prime.

2, 25, 3123, 823541, 285311670609, 302875106592251, 827240261886336764175, 1978419655660313589123977, 20880467999847912034355032910565, 2567686153161211134561828214731016126483467

Offset: 1

Author

Cino Hilliard, Nov 23 2003

Keywords

• nonn

Comments

Sum of reciprocals = 0.5403214192032919719402677251

Programs

Mathematica

#^#-2&/@Prime[Range[10]] (* Harvey P. Dale, Sep 22 2014 *)

PARI

ptop(n,m) = { sr=0; forprime(x=2,n, y=x^x-m; print1(y","); sr += 1.0/y; ); print(); print(sr) }

Formula

a(n) = A088730(n)-1=A088731(n)+1. - R. J. Mathar, Apr 26 2007