Multiplication is iterated addition\. $~$A \\cdot B \= A + A + A$~$\.\.\.\. $~$B$~$ times\.

If you look on Wikipedia's page about up arrow, they use the under-bracket notation, which looks much better.

by Alexei Andreev Jun 9 2016

Multiplication is iterated addition\. $~$A \\cdot B \= A + A + A$~$\.\.\.\. $~$B$~$ times\.

If you look on Wikipedia's page about up arrow, they use the under-bracket notation, which looks much better.