Functions and the Smallest Prime Factor

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Functions and the Smallest Prime Factor

by JJShannon3 » Sat Sep 01, 2012 6:57 am
I need some help on this one. Obviously, calculating out the product of all the even numbers between 2 and 100 is not the answer here. What's the shortcut? Thanks.

For every positive integer n, the function h(n) is defined to be the product of all the even integers from 2 to n, inclusive. If p is the smallest prime factor of h(100)+ 1, then p is
A. between 2 and 10
B. between 10 and 20
C. between 20 and 30
D. between 30 and 40
E. greater than 40

Answer is E.
Last edited by JJShannon3 on Sat Sep 01, 2012 7:19 am, edited 1 time in total.
Source: — Problem Solving |

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by JJShannon3 » Sat Sep 01, 2012 7:13 am
I keep getting to my answer being 2(50!)+ 1, but I'm lost on the smallest factor after that. The + 1 is throwing me off.

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by vk_vinayak » Sat Sep 01, 2012 7:18 am
- VK

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by neelgandham » Sat Sep 01, 2012 7:44 am
Please refer to my solution for this question here -> https://www.beatthegmat.com/gmat-prep-t97536.html
Mitch's solution here -> https://www.beatthegmat.com/tough-prime- ... 5475.html

Please let me know if you still need help with this!

vk_vinayak,
Thanks for the article. It is a very well written one indeed.
Anil Gandham
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by LalaB » Sat Sep 01, 2012 8:16 am
I never stop wondering why people dont use google. :)
Agree with a blank post of neelgandham. :) this question was discussed so many times that all we can add to that trillion posts is our blank posts :)
we wont say anything new; everything is already said
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