Блог пользователя Petr

Автор Petr, 10 лет назад, По-английски
  • Проголосовать: нравится
  • +38
  • Проголосовать: не нравится

»
10 лет назад, # |
  Проголосовать: нравится 0 Проголосовать: не нравится

In fact there are many generalizations of Cayley theorem (though I didn't know that particular one).

One was given as a problem on Putnam competition one year ago: http://www.artofproblemsolving.com/Forum/viewtopic.php?p=3315688&sid=56608f6bc111f1ce8bcfb33ff1220ce3#p3315688

Here is another one I know. Assume that we want to compute number of forests on n vertices with k trees such that vertices with indiced 1, ..., n belong to other trees. Then number of them is equal to knn - k - 1.

Despite the fact that there are many of them I always got problems even with proving basic version :p.