We know that a non-commutative ring may have different numbers of left ideals and two-sided ideals. For example, a matrix ring over a field has only 2 two-sided ideals but it have some non-trivial left ideals. My question is about the number of left ideals and right ideals. Does every non-commutative ring have the same numbers of left ideals and right ideals?
For another example, see the skew polynomial ring constructed in this solution: https://math.stackexchange.com/a/146406/29335
Given a field endomorphism $\rho: F\rightarrow F$ such that $[F:\rho(F)]\geq 2$, it produces a ring with exactly three left ideals and at least four right ideals.