# Find a prime factor of 99!-1

• Jun 7th 2005, 04:12 AM
cornoth
Find a prime factor of 99!-1
Find a prime factor of 99!-1
• Jun 14th 2005, 06:12 PM
hpe
Quote:

Originally Posted by cornoth
Find a prime factor of 99!-1

101, because 101 is prime and $99! \equiv -100! \equiv 1$ in $Z_{101}$
• Jun 16th 2005, 06:19 AM
cornoth
oh thats right, wilson's theorem.
thanks hpe!