SMUFD=BeBS=C 6 April 1966

Dr. Joshua Lederberg
Professor of Genetics
Stanford University
School of Medicine
Palo Alto, California

Dear Dr. Lederberg:

I would greatly appreciate having a copy of your Interin Report to
NASA (Grant NSG-81-60), Technical Report 1045 of your Instrumentation
Research Lab., entitled “Systematics of Srganic Molecules, Graph Topology
& Hamilton Circuits--A General Outline of the DENDRAL System", dated 12
January 1966.

The companion article on DENDRAL 64, "Topology of Cyclic Graphs--
A System for Computer Construction, Enumeration and Notation of Organte
Molecules as Tree Structures and Cyclic Graphs", dated 15 December 1965,
. &lso0 would be appreciated.

In 1955 I found a novel way to count Heinz & Blair's “free tree"
hydrocarbons directly--by partitioning the secondary Cily groups around
and between the branching (X or Y) points. Uave you tricd this route?
These structure models reveal new types of binomial cocfficients and
new types of partition-counting terms; at least my tables were novel
when checked by the international office of Unpublished Matheuccical
Tables at Stanford in 1956.

With best regards,
Wdlv

WILLTAN J, WISWESSER
Research Chemist

Crops Department
ec: Dr. R. A. Darrow P P

or. C. E. Minarik
Mr. W. H. Longenecker

ik