Math Is Fun Forum

simone

Member

Registered: 2007-10-05

Posts: 19

functions - logic

I need help with this, there must be a trick I'm missing. Thank you.

For every positive integer n, the function h(n) is defined as the product of all even integers from 2 to n, inclusive. If p is the smallest prime factor of   h(100)+1 , then p is

- between 2 and 10 ?
-between 10 and 20 ?
-between 20 and 30 ?
-between 30 and 40 ?
-grater than 40 ?

JaneFairfax

Member

Registered: 2007-02-23

Posts: 6,868

Re: functions - logic

The last one: greater than 40.

Hence every prime number less than 50 divides h(100) and so can’t be a factor of h(100)+1.

simone

Member

Registered: 2007-10-05

Posts: 19

Re: functions - logic

THANK YOU JANE!