perplexus.info :: Numbers : SUM = PR0DUCT

SUM = PR0DUCT (Posted on 2017-10-18)

List all the integers N, below 10000, such that the sum of their proper divisors (i.e. N excluded) equals their product.

Counterexample:
take 12: s(1,2,3,4,6)=16; p(1,2,3,4,6)=144;
so 12 is not on the list.

See The Solution Submitted by Ady TZIDON

No Rating

Comments: ( Back to comment list | You must be logged in to post comments.)

re: Analytic Solution..............revised

Comment 3 of 3 |

(In reply to Analytic Solution by Brian Smith)

IMHO - excellent proof!

I suggest editing the 1st sentence: either erase the word "at" or replace it by "at least".

Other than that - bravo!

Edited on October 19, 2017, 11:12 pm

Posted by Ady TZIDON on 2017-10-19 23:07:03

Please log in:

Forums (0)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (5)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:


perplexus dot info