\begin{definition}[Definition:Greek Numerals/Attic System]
The '''Greek numerals''' from the Attic period (c. 500 BCE to c. 300 BCE) are similar to the Roman system:
{{begin-eqn}}
{{eqn | l = \textsf{I}:
      | o = 
      | r = \)one\(
}}
{{eqn | l = \Pi:
      | o = \)'''penta'''\(:
      | r = \)five\(
}}
{{eqn | l = \Delta:
      | o = \)'''deka'''\(:
      | r = \)ten\(
}}
{{eqn | l = \Eta:
      | o = \)'''hekaton'''\(:
      | r = \)one hundred\(
}}
{{eqn | l = \Xi:
      | o = \)'''chilioi'''\(:
      | r = \)one thousand\(
}}
{{eqn | l = \Mu:
      | o = \)'''myriad'''\(:
      | r = \)ten thousand\(
}}
{{end-eqn}}
$\Pi$ was later written in a different form, with a shorter right leg, and from there it appears to have evolved into $\Gamma$.
Numbers were combined in a similar way to Roman numbers, but with additive forms only.
For example, $32718$ would have been written $\Mu \Mu \Mu \Xi \Xi \Eta \Eta \Eta \Eta \Eta \Eta \Eta \Delta \Pi \textsf {III}$.
Later evolutions introduced symbols for $50$, $500$ and $5000$, consisting of a tiny version of the appropriate power of $10$ nestled under the right hand (short) branch of the short-leg version of $\Pi$.
Such characters are difficult to render neatly, and as they are of limited importance, this has not been attempted on {{ProofWiki}}.
\end{definition}