## The Game of POP

No one knows how to live a funky life more than Prince:

Life, it ain’t real funky
Unless it’s got that pop

Need a little extra pop in your life? Here’s a game you can play.

Create a game board consisting of n adjacent squares. Here’s a board for n = 10:

Still with me? Good.

The rules of POP are rather straightforward.

1. Players alternate turns, placing either an O or a P in any unoccupied square.
2. The winner is the first player to spell the word POP in three consecutive squares.

I first learned this game using O’s and S’s and trying to spell SOS, but for young kids, O’s and P’s are much better… the accidental occurrences of POO and POOP add a certain je ne sais quoi. (But not as much as foreign phrases add to a sentence about feces.)

Alex and Eli played this game tonight on the board shown above. After six turns, the game was decided. (As you can see, an accidental POO occurred in squares 6‑8. I mean an accidental occurrence of the word POO, not an actual occurrence of POO itself. If the latter had happened, the game would have ended immediately, and I wouldn’t be writing about it now.) It was Alex’s turn, and he realized that he lost: playing either an O or a P in squares 3‑4 would give Eli the win, and playing either an O or P in squares 9‑10 would just delay the inevitable.

“So, what’re you gonna do?” I asked.

Alex added an O to the third square, shrugged, and handed the pencil to Eli.

A coward dies a thousand deaths; the valiant die but once.

In that game, Alex went first and lost. So an immediate question:

• Will the second player always win when n = 10?

This then leads to follow-up questions:

• Are there other values of n such that the second player has a winning strategy?
• Are there any values of n such that the first player has a winning strategy?
• Are there values of n for which neither player has a winning strategy?

If you’d like to play a game of POP, then head over to The Game of POP spreadsheet on Google Drive, email the link to your friend, and start adding O’s and P’s. Feel free to change the size of the game board, too! Just please be a sweetie — when you finish, clear all your letters, reset the size of the game board to 10 squares, and be sure all the directions are retained at the top of the page.

Enjoy!

## P (NFL ∪ Math) > 0

John Urschel is an offensive lineman for the Baltimore Ravens and admits, “I love hitting people.” As it turns out, he loves hitting the books, too. He earned a masters degree in mathematics from Penn State, and he recently published a paper with the impressive title A Cascadic Multigrid Algorithm for Computing the Fiedler Vector of Graph Laplacians in the Journal for Computational Mathematics.

Note that Urschel was the lead author, even though his three co-authors were an associate math professor from Tufts and two math professors from Penn State.

I have to wonder if the paper was fairly refereed. I mean, honestly, who in the math community is gonna tell a 6’3″, 308‑pound football player that he made an error?

A la Paul Erdös, Urschel doesn’t need much to be happy. In an essay published March 18, he wrote:

I’ll give you $1 if you didn’t. Is it a fair bet? Too easy? Then try this. Take your shoelaces and your friend’s shoelaces, fold them in half, and then expose the eight aglets. Choose two at a time and tie them together. The wager remains the same. Now is it fair? Is it possible to create a fair wager with any number of shoelaces? If so, how many? ## Passwords, Age Restrictions, and Computer Silliness My computer has been a bad boy recently. First, it told me that my password is going to expire approximately 11 months before I was born Interestingly, the folks at www.timeanddate.com disagree with the number of days between March 31, 1970, and the date that screen capture was snapped (March 1, 2015). So much for the truism that, “Computers make very fast, very accurate mistakes.” I thought the difference could be explained by excluding the end dates, but that doesn’t seem to be the case, so I’m not sure what ADPassMon is doing. (Then again, I’m not sure why I’m wasting my time checking the calculations of a piece of software whose warning messages suggest the existence of time travel.) Then, when attempting to register my sons for ski camp, it gave one of the craziest age restrictions I’ve ever seen… check out the valid ages… An age of 5.925 corresponds to 5 years, 11 months, 7 days, and 15 hours, which seems quite an arbitrary cut-off for a ski camp. Further, an age of 7.999 years means that kids are eligible for ski camp so long as they are not within 15 hours, 14 minutes, and 24 seconds of their eighth birthday. The framers of the Common Core would be happy with the consideration paid to MP.6: Attend to Precision. Where else have you seen ages expressed to the nearest thousandth? Not even parents of newborns use this many decimal places. Both of these issues remind me of a childhood friend who wanted to be a writer. He said he wanted to write stuff that would be widely read, cause an emotional reaction, and make people scream and cry. He now writes error messages for Microsoft. Here’s wishing you an error-free day! ## Deliver Us Not Into Bad Math What better way to celebrate National Pizza Day than sharing this sign, which hangs in our local Pizza Hut: Admittedly, I’ve never been very good with proportions, but even I know that $\frac{3}{14} \ne \frac{5}{30}$. Yet, that’s what’s implied by the statements for$3 and $5 in the sign. Further, • For$1, you can feed 4 children for 1 day. That’s a daily rate of 25.0¢ per child.
• For $3, you can feed 2 children for 7 days. That’s a daily rate of 21.4¢ per child. • For$5, you can feed 1 child for 30 days. That’s a daily rate of 16.7¢ per child.

Will the real price per child per day please stand up?

And then I took a look at that last statement — that \$10 can feed a classroom for a day — and it really blew my mind. Daily rates of 16.7 to 25.0¢ per child imply that classrooms have 40 to 60 students. I don’t know where these hungry students are, but maybe there should be a secondary campaign to reduce class size?

Though let’s be honest. What really seems to be needed here is an entirely new campaign:

## Can I Get Your Digits?

Saw this on a t-shirt recently:

Consider the number

1234567891011121314151617181920

obtained by writing the numbers from 1 to 20 in order side-by-side.

What’s the greatest number that can be obtained by crossing out 20 digits?

If a fetching lady or handsome gent catches your fancy by solving that problem, you might want to ask her or him…

How can I know so many digits of π and so few digits of your phone number?

And if he or she still hasn’t taken leave of you, then you could really press your luck with the following:

1. Ask your new friend to write down a number with four or more digits.

459,163

4 + 5 + 9 + 1 + 6 + 3 = 28

1. Subtract the sum from the original number.

459,163 – 28 = 459,135

1. Have your friend cross out one of the digits, and then read the remaining number aloud to you.

45,935

1. Then, miraculously announce the missing digit.

1

The secret to the trick? Simple. Just add the digits of the number that your friend reads aloud, and then figure out what number must be added to get the sum to a multiple of 9. Above, the digits of the number 45,935 have a sum of 26, which is 1 less than a multiple of 9, so the removed digit is 1.

The Math Jokes 4 Mathy Folks blog is an online extension to the book Math Jokes 4 Mathy Folks. The blog contains jokes submitted by readers, new jokes discovered by the author, details about speaking appearances and workshops, and other random bits of information that might be interesting to the strange folks who like math jokes.

## MJ4MF (offline version)

Math Jokes 4 Mathy Folks is available from Amazon, Borders, Barnes & Noble, NCTM, Robert D. Reed Publishers, and other purveyors of exceptional literature.