A Clojure project to try out various solutions to the N Queens problem.

A good introduction to this puzzle is found on Wikipedia:
  https://en.wikipedia.org/wiki/Nqueens

Another approach, using backtracking, is found beginning on page 203 of
The Icon Programming Language, 3rd Edition. The entire book is available
for download in PDF form from the University of Arizona at:
  https://www.cs.arizona.edu/icon/lb3.htm


Programs:
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permute-filter.clj	Diagonal tests based on Icon book algorithm.
permute-filter2.py	Python program from Wikipedia using much concise algorithm.
permute-filter2.clj	Port of Wikipedia Python program to Clojure.