"Euler thought no such 6-by-6 square exists, recently the game has changed. In a paper posted online and submitted to Physical Review Letters, a group of quantum physicists in India and Poland demonstrates that it is possible to arrange 36 officers in a way that fulfills Euler’s criteria — so long as the officers can have a quantum mixture of ranks and regiments."
"Euler thought no such 6-by-6 square exists, recently the game has changed. In a paper posted online and submitted to Physical Review Letters, a group of quantum physicists in India and Poland demonstrates that it is possible to arrange 36 officers in a way that fulfills Euler’s criteria — so long as the officers can have a quantum mixture of ranks and regiments."