Quasigroup
A groupoid
such that for all
, there exist unique
such that
|
(1)
| |||
|
(2)
|
No other restrictions are applied; thus a quasigroup need not have an identity element, not be associative, etc. Quasigroups are precisely groupoids whose multiplication tables are Latin squares. A quasigroup can be empty.
1000th twin prime