Rough Pythagorean fuzzy ideals in ternary semigroups
Ronnason Chinram, Thammarat Panityakul · Journal of Mathematics and Computer Science · 2020
A ternary semigroup is a nonempty set equipped with an associative ternary operation. A Pythagorean fuzzy set is one of the generalizations of the fuzzy set. The aim of this paper is to study rough Pythagorean fuzzy ideals in ternary semigroups. This idea is extended to the lower and upper approximations of Pythagorean fuzzy ideals.