I added a function, prog2int, to brute_big.ml. Its purpose is to say what number corresponds to a program. For instance,

# prog2int lrpnwords ['1';'+';'s';'1';'+';'s'];;
- : string = "128766050"

I also added an optional argument to "discover", so that you don't always have to begin a search at 0.

discover ~minnum:(Big_int.big_int_of_string "120000000") ~maxnum:(Big_int.big_int_of_string "150000000")

would give a range that could find ['1';'+';'s';'1';'+';'s'].

Jeff