Mensaje citado por: John McCarthy <jmc@steam.Stanford.EDU>:
When two sets are proved to have the same number of elements, e.g. the number of partitions of n into odd parts and the number of partitions of n into distinct parts, it seems natural to ask whether the proof should be given by establishing a 1-1 correspondence between the sets. ...
We can ask whether there is a "canonical" 1-1 correspondence. [...]
There is another nice example of this in group representation theory where the number of classes equals the number of irreducible representations. It is tempting to asssociate the identity class with the unit representation, but much anguish has been expended trying to extend such a concept. - hvm ------------------------------------------------- Obtén tu correo en www.correo.unam.mx UNAMonos Comunicándonos