Every Monday from now until whenever! Fact: saying the words "four factorial matrix" makes you sound douchey and aloof. Why not do it more often? Here are all the permutations written out. 1234 1243 1324 1342 1423 1432 2134 2143 2314 2341 2413 2431 3124 3142 3214 3241 3412 3421 4123 4132 4213 4231 4312 4321