Ph.D. in Mathematics, Princeton University, 1965. Author of many published papers in mathematics journals. For links to them, please visit my homepage http://home.earthlink.net/~jsondow/ which also displays many beautiful formulas and plots.
We were saddened to hear that Jonathan Sondow passed away on January 16 2020 at the age of 77. There is an obituary notice in the University of Wisconsin Alumni Association written by his son Joe: https://www.uwalumni.com/alumninote/jonathan-sondow/ - N. J. A. Sloane 22:28, 16 May 2020 (EDT)