Euler 005

Sorry for three in one day, but this one was awesome in Haskell.

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?

Neil, you might punch me for this one.

 a=foldl1 lcm [1..20]

I am sorry Haskell has a built-in LCM function. 21 characters.