Proposed by Toby Walsh
An order m quasigroup is a Latin square of size m. That is, a $m \times m$ multiplication table in which each element occurs once in every row and column. For example,
1 2 3 4
4 1 2 3
3 4 1 2
2 3 4 1
is an order 4 quasigroup. A quasigroup can be specified by a set and a binary multiplication operator, * defined over this set. Quasigroup existence problems determine the existence or non-existence of quasigroups of a given size with additional properties. Certain existence problems are of sufficient interest that a naming scheme has been invented for them. We define two new relations, *321 and *312 by $a *321 b = c$ iff $c*b=a$ and $a *312 b = c$ iff $b*c=a$.
QG1.m problems are order m quasigroups for which if $a*b=c$, $a*b=c*d$ and $a *321 b = c *321 d$ then $a=c$ and $b=d$.
QG2.m problems are order m quasigroups for which if a*b=c*d and a *312 b = c *312 d then a=c and b=d.
QG3.m problems are order m quasigroups for which $(a*b)*(b*a) = a$.
QG4.m problems are order m quasigroups for which $(b*a)*(a*b) = a$.
QG5.m problems are order m quasigroups for which $((b*a)*b)*b = a$.
QG6.m problems are order m quasigroups for which $(a*b)*b = a*(a*b)$.
QG7.m problems are order m quasigroups for which $(b*a)*b = a*(b*a)$.
For each of these problems, we may additionally demand that the quasigroup is idempotent. That is, a*a=a for every element a.