Computing Left Kan Extensions Using the Todd-Coxeter Procedure

  • M. Leeming
  • R. F. C. Walters
Part of the Mathematics and Its Applications book series (MAIA, volume 325)


The procedure described by Todd and Coxeter [8] 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 [4]). 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.


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Copyright information

© Springer Science+Business Media Dordrecht 1995

Authors and Affiliations

  • M. Leeming
    • 1
  • R. F. C. Walters
    • 1
  1. 1.Department of MathematicsUniversity of SydneySydneyAustralia

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