Monthly Archives: July 2016

Twisty lattice paths, all alike

I haven’t posted a puzzle in quite a while, so… Every morning, I drive from my home at 1st and A to my work at 9th and J (8 blocks east and 9 blocks north), always heading either east or … Continue reading

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Recently my wife and I saw a double rainbow, shown below.  I’m a lousy photographer, but it’s there if you look closely, along the top of the picture: There are plenty of existing sources that describe the mathematics of rainbows: … Continue reading

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