N ov 2 00 5 Combinatorics and distributions of partial injections
نویسنده
چکیده
We obtain several combinatorial results about chains, cycles and orbits of the elements of the symmetric inverse semigroup ISn and the set Tn of nilpotent elements in ISn. We also get some estimates for the growth of |ISn| and |Tn|, and study random products of elements from ISn.
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