Existence of left invariant measures on a semigroup S with definitions of m(A)=m(xA) or m({y:y belong to xA}) does not mean that support m is right group because it could be embedded in right group, i.e. direct product of semigroup embeddable in a group and right nulls semigroup. But even later description does not equivalent existence of left invariant measure on left cancellable semigroup beca use it required Malcev conditions.
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