Re: [Haskell-cafe] speeding up fibonacci with memoizing

Besides memoizing, you might want to use the fact that: fib (2*k) == (fib (k+1))^2 - (fib (k-1))^2 fib (2*k-1) == (fib k)^2 + (fib (k-1))^2 Regards, Yitz