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Perfect semigroups

Published online by Cambridge University Press:  20 January 2009

John Fountain
Affiliation:
University of York, Heslington, York Y01 5DD
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A semigroup S with identity is (left) perfect if every unitary left S-system has a projective cover. This is the semigroup analogue of the definition of left perfect rings introduced in (1). The investigation of perfect semigroups was initiated by Isbell (4), who proved that a semigroup is perfect if and only if it satisfies two conditions referred to as conditions A and D.

Type
Research Article
Copyright
Copyright © Edinburgh Mathematical Society 1976

References

REFERENCES

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