2520 is the smallest number that can be divided by each of the numbers from 1 to 10 without any remainder. What is the smallest positive number that is evenly divisible by all of the numbers from 1 to 20?
- Problem 5 of the Euler series of problems.
I had to bite hard to solve problem 4: ( find the largest numerical palindrome which is the product of two three digit numbers.) Mathematics, like programming or playing an instrument, is something you have to practice =every day=. Doing problems you have solved before doesn't make you any better.
About M381 and the URM. There is a Java program called JURM written by Charlton D. Rose and is available for download, including source. Have fun! Compliments to the author. http://charltonrose.com/school/jurm/
More interesting software. http://www.mnemosyne-proj.org/ Mnemosyne is the open source version of Supermemo. I have written several times about Supermemo and efficient studying. The big plus of Mnemosyne is that you can use LaTeX on the flashcards.
Mathematica programming is not restricted to one paradigm like Java which enforces you to use Object Oriented programming. With Mathematica you can do Functional programming, Procedural programming, Rule-based programming and Object Oriented programming. I am close to entering the realm of rule-based programming. Used by programming experts as the paradigm of choice and unleashes the real power of Mathematica. More on this to follow.