Computing Left Kan Extensions Using the Todd-Coxeter Procedure
The procedure described by Todd and Coxeter  is a mechanical technique for the enumeration of group cosets. The method has numerous applications within group theory (see the examples in Coxeter and Moser ). Carmody and Walters [2, 3] gave a generalised procedure relating to the construction of certain left Kan extensions. Of this procedure, the Todd-Coxeter method is a special case. This paper describes a further generalisation, extending the procedure to the construction of left Kan extensions of finite product preserving functors. The introduction of products involves a substantial increase in the complexity of the procedure. However, the benefit derived from the additional generality is substantial.
KeywordsPartial Function Generate Object Left Hand Column Hand Column Complete Presentation
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