**Choose your language.**I write in English, but I translate many of my articles to Czech as well.

**Zvolte si jazyk.**Píšu anglicky, ale řadu svých článků překládám i do češtiny.

# Aleph-Null Bottles Of Beer On The Wall

Let’s quickly recap the most important (and weird) properties of the “natural numbers infinity” we call <$\aleph_0$>.

Welcome to another part of the “Maths For Normal People” series. You will find all the previous parts in this article.

So far, we have derived the following strange facts (<$n$> stands for an arbitrary natural number, e.g. <$1, 2, 3, 4,\ldots$>).

<$$ \displaylines{ \aleph_0 + n = \aleph_0 \\ \aleph_0 - n = \aleph_0 \\ \aleph_0 \cdot n = \aleph_0 \\ \frac{\aleph_0}{n} = \aleph_0 \\ \aleph_0 - \aleph_0 \text{ makes no sense!} } $$>The apparent absurdity of infinity can be summed up by this truth:

<$$ \aleph_0 - 1 = \aleph_0 $$>Sounds difficult? Let me put that in a song. Know 99 Bottles of Beer?

Aleph-null bottles of beer on the wall, Aleph-null bottles of beer,

Take one down, and pass it around, Aleph-null bottles of beer on the wall.

Aleph-null bottles of beer on the wall, Aleph-null bottles of beer,

Take one down, and pass it around, Aleph-null bottles of beer on the wall.

Aleph-null bottles of beer on the wall, Aleph-null bottles of beer,

Take one down, and pass it around, Aleph-null bottles of beer on the wall.

<$$ \vdots $$>

You just keep singing as long as there are any bottles left ;-)

Want to read more? You will find the outline of all parts of the series in this article.