On 6/7/11 7:31 AM, Florent Hivert wrote:
       Hi there,

I'm working with Dyck words and binary trees and I'm looking for name for the
following functions:

   - for a dyck word [1,1,0,0,1,0], return its reversed, exchanging open to
     close [1,0,1,1,0,0]

You could call this Schuetzenberger involution; on words it complements and 
then reverses
all letters.

   - for a binary tree, recursively exchange left and right branches.

for a dyck word dw (considered as a path):

   - the x coordinate of the point of height 0

Do you mean points, not point, since there could be several?

   - the number of opening parentheses at the beginning of dw

initial_rise?

Cheers,

Anne

--
You received this message because you are subscribed to the Google Groups 
"sage-combinat-devel" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to 
[email protected].
For more options, visit this group at 
http://groups.google.com/group/sage-combinat-devel?hl=en.

Reply via email to