Hello Greg, Thursday, December 22, 2005, 8:15:08 PM, you wrote: GB> You might also like to try the slightly more efficient... GB> pyth n = [(a,b,c) | a <- [1..n], GB> b <- [a..n], GB> c <- [a+1..n], "c <- [b+1..n]" is even better :) GB> a*a + b*b == c*c ] -- Best regards, Bulat mailto:bulatz at HotPOP.com