Pebbling a Chessboard (even more) - Numberphile |
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Description: MAIN VIDEO: http://youtu.be/lFQGSGsXbXE CONTINUATION: http://youtu.be/qbkH_0TNdk0 AND EVEN MORE: http://youtu.be/uENSO785aEI PLUS CUT FROM PART ONE: http://youtu.be/hggcjvdCihc Featuring Zvezdelina Stankova - Professor of Mathematics at Mills College, Director of Berkeley Math Circle, UC Berkeley Spreading clones across chessboard and escaping "prison" - commonly known as pebbling a chessboard. Check these papers: http://bit.ly/pebblechess1 http://bit.ly/pebblechess2 With thanks to the Mathematical Sciences Research Institute - MSRI --- Videos by Brady Haran A POSTSCRIPT ON THIS VIDEO FROM PROFESSOR STANKOVA When you asked me if all inescapable prison shapes should be like the wedge-type we studied. Unfortunately, the asymmetric shape that I drew that could, in principle, be a "minimal inescapable prison" (it contained 9 cells): x x x xxx xxx is not minimal since it does contain the 6-cell wedge prison that we showed in the second clip (Part II) that is inescapable. Should have drawn something else, like: x x x xx xx in other words, chop off the two rightmost cells. 
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