Аннотация:
The paper presents a full description of idempotent elements of
the semigroup of binary relations $B_{X}(D)$, which are defined by
semilattices of the class $\Sigma_{3}(X,8)$. For the case where
$X$ is a finite set and $Z_{7}=\varnothing$, we derive formulas
for calculating the number of idempotent elements of the
respective semigroup.
