Neophyte/Unoptimized version of Euler Number 42 in Common Lisp
;; ********************************************** ;; Author: Berlin Brown <berlin dot brown @ gmail.com> ;; Overview: Euler Example Number 42 (neophyte version) ;; Target Environment: Common Lisp -> Clisp/Sbcl ;; Date: 5/19/2008 ;; -------------- ;; The nth term of the sequence of triangle numbers is given ;; by, tn = 0.5 * n * (n+1); so the first ten triangle numbers are: ;; ;; 1, 3, 6, 10, 15, 21, 28, 36, 45, 55, ... ;; ;; By converting each letter in a word to a number corresponding to ;; its alphabetical position and adding these values we form a word value. ;; For example, the word ;; value for SKY is 19 + 11 + 25 = 55 = t10. If the word value ;; is a triangle number then we shall call the word a triangle word. ;; ;; Using words.txt (right click and 'Save Link/Target As...'), ;; a 16K text file containing nearly two-thousand common English words, ;; how many are triangle words? ;; ;; References: ;; [1] http://www.lispworks.com/documentation/HyperSpec/Front/X_Maste