A060679 Orders of non-cyclic groups.

4, 6, 8, 9, 10, 12, 14, 16, 18, 20, 21, 22, 24, 25, 26, 27, 28, 30, 32, 34, 36, 38, 39, 40, 42, 44, 45, 46, 48, 49, 50, 52, 54, 55, 56, 57, 58, 60, 62, 63, 64, 66, 68, 70, 72, 74, 75, 76, 78, 80, 81, 82, 84, 86, 88, 90, 92, 93, 94, 96, 98, 99, 100, 102, 104, 105, 106, 108

Offset: 1

Author

Ahmed Fares (ahmedfares(AT)my-deja.com), Apr 19 2001

Keywords

• nonn

Comments

Numbers n such that x^n==1 (mod n) has solutions 2<=x<=n - Benoit Cloitre, May 10 2002

Links

• Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

Crossrefs

Complement of A003277.

Programs

PARI

is(n)=gcd(n,eulerphi(n))>1 \\ Charles R Greathouse IV, Apr 16 2012

Formula

a(n) = n + O(n/log log log n). - Charles R Greathouse IV, Apr 16 2012

Extensions

More terms from Vladeta Jovovic, Jul 05 2001