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@@ -36,7 +36,8 @@ Some are in Jupyter (IPython) notebooks, some in `.py` files. You can view the f
 |[The Puzzle of the Misanthropic Neighbors](ipynb/Mean%20Misanthrope%20Density.ipynb)&nbsp; &nbsp; **[NB](http:/nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Mean%20Misanthrope%20Density.ipynb)**, **[DN](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FMean%2520Misanthrope%2520Density.ipynb)**<br>*How crowded will this neighborhood be, if nobody wants to live next door to anyone else?*|
 |[Four 4s, Five 5s, and Countdown to 2016](ipynb/Countdown.ipynb)&nbsp; &nbsp; **[NB](http:/nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Countdown.ipynb)**, **[DN](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FCountdown.ipynb)**<br>*Solving the equation 10 _ 9 _ 8 _ 7 _ 6 _ 5 _ 4 _ 3 _ 2 _ 1 = 2016. From an Alex Bellos puzzle.*|
 |[Sicherman Dice](ipynb/Sicherman%20Dice.ipynb)&nbsp; &nbsp; **[NB](http:/nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Sicherman%20Dice.ipynb)**, **[DN](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FSicherman%2520Dice.ipynb)**<br>*Find a pair of dice that is like a regular pair of dice, only different.*|
-|[Sol Golomb's Rectangle Puzzle](ipynb/Golomb-Puzzle.ipynb)&nbsp; &nbsp; **[NB](http:/nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Golomb-Puzzle.ipynb)**, **[DN](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FGolomb-Puzzle.ipynb)**<br>*A Puzzle involving placing rectangles of different sizes inside a square. Bonus: cryptarithmetic.*|
+|[Sol Golomb's Rectangle Puzzle](ipynb/Golomb-Puzzle.ipynb)&nbsp; &nbsp; **[NB](http:/nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Golomb-Puzzle.ipynb)**, **[DN](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FGolomb-Puzzle.ipynb)**<br>*A Puzzle involving placing rectangles of different sizes inside a square.*|
+|[Cryptarithmetic](ipynb/Cryptarithmetic.ipynb)&nbsp; &nbsp; **[NB](http:/nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Cryptarithmetic.ipynb)**, **[DN](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FCryptarithmetic.ipynb)**<br>*Substitute digits for letters and make NUM + BER = PLAY.*|
 |[The Riddler: Battle Royale](ipynb/Riddler%20Battle%20Royale.ipynb)&nbsp; &nbsp; **[NB](http:/nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Riddler%20Battle%20Royale.ipynb)**, **[DN](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FRiddler%2520Battle%2520Royale.ipynb)**<br>*A puzzle involving allocating your troops and going up against an opponent.*|
 
 |Word Games|