# [Tutor] project euler prime factorization problem

Nick nblack3 at student.gsu.edu
Sun Aug 29 23:58:48 CEST 2010

```"Did you test the program? That is one way to tell whether it works perfectly. What you showed above will do one visible thing - it will print "Don't forget to consider primes 2, 3, 5, and 7\n". The rest is a somewhat confusing collection of function definitions and comments. You never call the functions so nothing else will happen.

As Alan said - research prime factors to see how others approach it.

My current reasoning was something of this sort:  Find all the factors of a number, then reduce them to just the prime factors

Very inefficient. IMHO the proper way is to generate a list of all the prime numbers up to the square root of 600851475143, then test each (starting with the largest and working down) till you discover a factor. That then is the answer.

There are many published algorithms for generating primes.

and you can then multiply them together to get that number thus having the prime factors.  I need a lot of help haha.  Thanks in advance everyone.  If anyone has a good resource to point me to other than the open book project and dive into python it would be much appreciated.  Would it be useful for me to buy a book, and if so what are some easily accessible ones?  I feel dive into python is just too advanced for me.  I understand a lot of the teachings, but the examples seem unwieldy and esoteric.

--
Bob Gailer
"