sequences that are permutations

N. J. A. Sloane njas at research.att.com
Sat Oct 13 21:45:14 CEST 2001


Howard Landman <howard at polyamory.org> has put together a preliminary
list of the sequences that are permutations of the natural numbers
(or in some cases of the nonnegative integers).

Here is the current version.  If anyone knows of other examples,
please send them to me (njas).

The entries in the index will also be updated.

Sequence-Inverse	
A000027	- self-inverse
A002251	- self-inverse	
A003100	- self-inverse	
A003188	- A006068
A004484	- A064206	
A004485	- A064207	
A004486	- A064208	
A004487	- A064211	
A019444	- self-inverse	
A026243	- self-inverse	
A029654	- A064360	
A064413 - A064664
A032447	- A064275	
A035312	- A035358
A035506	- A064357	
A035513	- A064274	
A047708	- A048850	
A048647	- A064212	
A048672	- A064273	
A048673	- A064216	
A048679	- A048680	
A052330	- A064358	
A059900 - A059884
A052331	- A064359	
A054238	- A054239	
A054424	- A054426	
A054427	- A054428	
A054429	- self-inverse	
A054430	- self-inverse	
A054081	- n/a		array: rows are permutations but it isn't itself

I think the squares of these permutations also should be in the database.
I suggested this to Howard, but this is a big job and if anyone else would
be willing to send in some "squares" that would be very helpful.

If f is one of the permutations mentioned above
then what I mean is the sequence
f(f(1)), f(f(2)), f(f(3)), f(f(4)), ...
- except perhaps beginning with f(f(0)) if that is appropriate.

Of course many of these may already be in the database; if so this should be noted.

Neil Sloane






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