To calculate (2), it helps to visualize the $S_n$ as the successive positions in a random walk.
The knowledge of the invariant subspaces of an operator helps us to visualize its action.
Go to the list of words starting with: a
Copyright © 2011 by Jerzy Trzeciak, Warszawa 2011. All rights reserved.
Copyright © 2006-2011 by IMPAN. All rights reserved.
Copyright © 2006-2012 by IMPAN. All rights reserved.