Left Ore set
= Left Ore set
A <multiplicative set> $S$ in a <ring> $R$, with $1\in S$ and $0\notin S$, is left Ore when, for every $s\in S$ and $r\in R$, there are $s'\in S$ and $r'\in R$ such that $s'r=r's$.
= Left Ore set
A <multiplicative set> $S$ in a <ring> $R$, with $1\in S$ and $0\notin S$, is left Ore when, for every $s\in S$ and $r\in R$, there are $s'\in S$ and $r'\in R$ such that $s'r=r's$.