haskell memo

h = 1:map (2*) h # map (3*) h # map(5*) h
where xxs@(x:xs) # yys@(y:ys)
| x==y =x:(xs#ys)
| x<y  =x:(xs#yys)
| x>y  =y:(xxs#ys)
prime = let p (x:xs) =x:(p (filter ((/=).(flip rem x)) xs))
in p [2..]
fib = :1:[i+j|(i,j)<-zip fib $tail fib]
More Reading
Newer// halftone
Older// SPRINT