gistfile1.hs

a (m,n) | m==0        = n+1
        | m>0 && n==0 = a(m-1,1)
        | m>0 && n>0  = a(m-1,a(m,n-1))

k c n d | n == 0     = c*d
        | n == 1     = c^d
        | d == 0     = 1
        | otherwise  = k c (n-1) $ k c n (d-1)

g = (!!63) $ iterate (\ n -> k 3 n 3) 4

main = return (a(g,g))
   >>= putStrLn . show