Tag Archives: proof

What would Dijkstra do? Proving the associativity of min

This semester I’m teaching a Discrete Mathematics course. Recently, I assigned them a homework problem from the textbook that asked them to prove that the binary operator on the real numbers is associative, that is, for all real numbers , … Continue reading

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Pan-Galactic Division in Haskell

Summary: given an injective function , it is possible to constructively “divide by ” to obtain an injection , as shown recently by Peter Doyle and Cecil Qiu and expounded by Richard Schwartz. Their algorithm is nontrivial to come up … Continue reading

Posted in haskell, math, species | Tagged , , , , , , , , , | 6 Comments