Editing Multiplication algorithm (section)

====Examples ====
Below is a lookup table of quarter squares with the remainder discarded for the digits 0 through 18; this allows for the multiplication of numbers up to {{math|9×9}}.

{| border="1" cellspacing="0" cellpadding="3" style="margin:0 0 0 0.5em; background:#fff; border-collapse:collapse; border-color:#7070090;" class="wikitable"
|- style="text-align:right;"
|{{math|''n''}}&nbsp;&nbsp; || &nbsp;&nbsp;0 || &nbsp;&nbsp;1 || &nbsp;&nbsp;2 || &nbsp;&nbsp;3 || &nbsp;&nbsp;4 || &nbsp;&nbsp;5 || &nbsp;&nbsp;6 || 7 || 8 || 9 || 10 || 11 || 12 || 13 || 14 || 15 || 16 || 17 || 18
|- style="text-align:right;"
|{{math|⌊''n''<sup>2</sup>/4⌋}} || 0 || 0 || 1 || 2 || 4 || 6 || 9 || 12 || 16 || 20 || 25 || 30 || 36 || 42 || 49 || 56 || 64 || 72 || 81
|}

If, for example, you wanted to multiply 9 by 3, you observe that the sum and difference are 12 and 6 respectively. Looking both those values up on the table yields 36 and 9, the difference of which is 27, which is the product of 9 and 3.