-- Consider all integer combinations of a^b for 2 ≤ a ≤ 5 and 2 ≤ b ≤ 5: -- -- 2^2=4, 2^3=8, 2^4=16, 2^5=32 -- 3^2=9, 3^3=27, 3^4=81, 3^5=243 -- 4^2=16, 4^3=64, 4^4=256, 4^5=1024 -- 5^2=25, 5^3=125, 5^4=625, 5^5=3125 -- If they are then placed in numerical order, with any repeats removed, -- we get the following sequence of 15 distinct terms: -- -- 4, 8, 9, 16, 25, 27, 32, 64, 81, 125, 243, 256, 625, 1024, 3125 -- -- How many distinct terms are in the sequence generated by ab for 2 ≤ a ≤ 100 and 2 ≤ b ≤ 100? import Data.List (nub) main = print (length $ nub [a ^ b | a <- [2..100], b <- [2..100]])