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+;;  Copyright (c) Stephen C. Gilardi. All rights reserved.
+;;  The use and distribution terms for this software are covered by the
+;;  Common Public License 1.0 (http://opensource.org/licenses/cpl.php)
+;;  which can be found in the file CPL.TXT at the root of this distribution.
+;;  By using this software in any fashion, you are agreeing to be bound by
+;;  the terms of this license.
+;;  You must not remove this notice, or any other, from this software.
+;;
+;;  lazy-seqs.clj
+;;
+;;  Lazy sequences
+;;
+;;  primes - based on the "naive" implemention described in [1] plus a
+;;           small "wheel" which eliminiates multiples of 2, 3, 5, and
+;;           7 from consideration by incrementing past them. Also inspired
+;;           by code from Christophe Grand in [2].
+;;
+;;  fib    - based on code from Rich Hickey at the Clojure wiki [3]  
+;;
+;;  [1] http://www.cs.hmc.edu/~oneill/papers/Sieve-JFP.pdf
+;;  [2] http://clj-me.blogspot.com/2008/06/primes.html
+;;  [3] http://en.wikibooks.org/wiki/Clojure_Programming#Examples
+;;
+;;  scgilardi (gmail)
+;;  07 June 2008
+
+(clojure/in-ns 'lazy-seqs)
+(clojure/refer 'clojure)
+
+(lib/use def)
+
+(defvar primes
+  (lazy-cat [2 3 5 7]
+    (let [primes-from
+		  (fn primes-from [n [f & r]]
+			(if (some #(zero? (rem n %)) (take-while #(<= (* % %) n) primes))
+			  (recur (+ n f) r)
+			  (lazy-cons n (primes-from (+ n f) r))))
+		  wheel (cycle [2 4 2 4 6 2 6 4 2 4 6 6 2 6  4  2
+						6 4 6 8 4 2 4 2 4 8 6 4 6 2  4  6
+						2 6 6 4 2 4 6 2 6 4 2 4 2 10 2 10])]
+	  (primes-from 11 wheel)))
+  "A lazy sequence of all the prime numbers.")
+
+(defvar fib
+  (concat [0 1]
+    (let [rest-fn
+		  (fn rest-fn [a b]
+			(let [next (+ a b)]
+			  (lazy-cons next (rest-fn b next))))]
+	  (rest-fn 0 1)))
+  "A lazy sequence of all the fibonacci numbers.")