You can also recursively define fib as a lazy sequence that is the pairwise sum of fib and fib shifted by one. (Clojure, from Rosetta Code). (def fib (lazy

You can also recursively define fib as a lazy sequence that is the pairwise sum of fib and fib shifted by one. (Clojure, from Rosetta Code). (def fib (lazy-cat [0 1] (map + fib (rest fib)))) => (take 10 fib) (0 1 1 2 3 5 8 13 21 34) Explanation: 0 1 1 2 3 5 ; this is fib + 1 1 2 3 5 8 ; this is (rest fib) --------------- 1 2 3 5 8 13 ; this is (map + fib (rest fib)) ; and the sequence needs to be initialized with (lazy-cat [0 1] ...