Tree numbers

Fri May 30 11:28:01 CDT 2003

Dear members
The number of phologenetic trees possible increases geometrically when the number of taxa increases: 3 trees for 3 taxa, 15 trees for 4 taxa, 105 trees for 5 taxa, and so. Can any colleague give me the formula to calculate the number of trees possible for a cetain number of taxa.
Gurcharan Singh
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Dr. Gurcharan Singh
Department of Botany                  Res. 932 Anand Kunj
S. G. T. B. Khalsa College                    Vikas Puri
University of Delhi                                 New Nelhi-110018
Delhi-110007, INDIA                            INDIA
Phone: 27666469                                Phone: 25531534, 9810359089
                       mail: singhg at satyam.net.in
                               chani at sify.com
                               singhg45 at yahoo.co.uk
                               singhg at khalsacollegedu.com
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