For quite a while the two of us sat at our table, wordlessly stirring our coffee. Ervinke was bared. All right,
he said. Let’s play poker.
No,
I answered. I hate cards. I always lose.
Who’s talking about cards?
thus Ervinke. I was thinking of Jewish poker.
He then briefly explained the rules of the game. Jewish poker is played without cards, in your head, as befits the People of the Book.
You think of a number, I also think of a number,
Ervinke said. Whoever thinks of a higher number wins. This sounds easy, but it has a hundred pitfalls. Nu!
All right,
I agreed. Let’s try.
We plunked down five piasters each, and, leaning back in our chairs began to think of numbers. After a while Ervinke signaled that he had one. I said I was ready.
All right,
thus Ervinke. Let’s hear your number.
Eleven,
I said.
Twelve,
Ervinke said, and took the money.
I could have’ kicked myself, because originally I had thought of Fourteen, and only at the last moment had I climbed down to Eleven, I really don’t know why. Listen.
I turned to Ervinke. What would have happened had I said Fourteen?
What a question! I’d have lost. Now, that is just the charm of poker: you never know how things will turn out. But if your nerves cannot stand a little gambling, perhaps we had better call it off.
…
Jewish Poker by Ephraim Kimshon
. But you can also take any tetrahedron to any other tetrahedron, leading to conjugate copies of the same group. Those are 5 copies. Hence, what you obtain finally is the alternating group 
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For a cup of coffee more 