We show that all subvarieties of left regular bands are closed in the variety of all bands. We
also show that all subvarieties of left seminormal bands are saturated in the variety of all …

We show that all subvarieties of the variety of rectangular bands are closed in the variety of
all bands. Further, we show that the variety of regular bands is closed. Next, we introduce …

We show that any almost unitary subsemigroup of a semigroup is closed in the containing
semigroup and that the class of all left [right] regular semigroups is closed. Finally, we show …

It is well known that every subvariety of the variety of semigroups need not be absolutely
closed. Thus, identifying those subvarieties that are closed in themselves or in larger …

We show that all subvarieties of the variety of rectangular bands are closed in the variety of $
n $-nilpotent extension of bands. Ahanger, Nabi and Shah in [1] have proved that the variety …

We show that for each n≥ 2∈ N, the varieties V n=[x 1 x 2 x 3= x 1 nxi 1 xi 2 xi 3] where i is
any non-trivial permutation of {1, 2, 3} are closed. Further, we show that for each n∈ N, the …

We show that the class of permutative semigroups (medial semigroups) satisfying the
homotypical identity [axy= axay] is saturated and, as a corollary, we found that an externally …

Epimorphisms Amalgams and Po-Unitary Pomonoids Next Article in Journal Influence of a
Given Field of Temperature on the Blood Pressure Variation: Variational Analysis …

Some Closed Varieties of Semigroups Page 1 Palestine Journal of Mathematics Vol. 12(3)(2023)
, 52–64 © Palestine Polytechnic University-PPU 2023 Some Closed Varieties of …

In this paper, we first show that the variety 𝒱 of posemigroups satisfying an identity axy=
axay is closed if it is 𝒱-convex. Next, we show that inverse posemigroups satisfying an …