Go backward to ExponentiationGo up to TopGo forward to Examples |

`x`*divides*`y`if`x`*`z`=`y`for some`z`:`x`|`y`: <=>**exists**`z`:`x`*`z`=`y`.- The
*greatest common divisor*of`x`and`y`is the largest number that divides both`x`and`y`:gcd(

`x`,`y`) :=**such**z:`z`|`x`/\`z`|`y`/\ (**forall**w: (`w`|`x`/\`w`|`y`) =>`w`<=`z`). - The
*least common multiple*of`x`and`y`is the smallest number that both`x`and`y`divide:lcm(

`x`,`y`) :=**such**z:`x`|`z`/\`y`|`z`/\ (**forall**w: (`x`|`w`/\`y`|`w`) =>`z`<=`w`).

Author: Wolfgang Schreiner

Last Modification: November 16, 1999