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The Joshua Lederberg Papers

Title:
Letter from Joshua Lederberg to Victor Klee pdf (101,463 Bytes) transcript of pdf
Letter from Joshua Lederberg to Victor Klee
Description:
Item is handwritten. Item is a photocopy.
Number of Image Pages:
2 (101,463 Bytes)
Date:
1976-03-18 (March 18, 1976)
Creator:
Lederberg, Joshua
Recipient:
Klee, Victor
Rights:
This item is in the public domain. It may be used without permission.
Relation:
Lederberg Grouping: No Epoch
Box Number: 58
Folder Number: 24
Unique Identifier:
BBGGVZ
Accession Number:
48
Document Type:
Letters (correspondence)
Language:
English
Format:
application/pdf
image/tif
Physical Condition:
Good
Series: Research
SubSeries: Computer Science
SubSubSeries: DENDRAL (Dendritic Algorithm)
SubSubSubSeries: Systems Architecture (Mathematical Foundations)
SubSubSubSubSeries: Diagrams and Tree Structures
Folder: "A4 Symmetry", 1975-1976
Transcript:
[stamped, Mar 18 1975]
Dear Victor
Thank you for sending me Jim Laurence's answer to the problem I posed to you in my letter of 3/31/75 (copy enclosed.) Hardly anything bearing exactly on this question has been published: the 2 enclosed reprints may say something of the background (labeling; CONGEN).
The molecular structures that CONGEN builds ignore stereoisomers (for the present): i.e., they classify the C atom as S4. At one time I wanted to categorize some stereoisomers. Instead of re-writing the basic program, I thought I would substitute an A4 graph in place of C; the program would then calculate the appropriate symmetries, albeit at some cost in computational efficiency.
Hence the question: what is the smallest A4.
You should note that Ray Carhart had already produced a 2l-node graph, and I thought I had sent that to you. We did not know whether this was the smallest With slings ([diagram]) and higher values we also find one at 22 nodes;
[END PAGE ONE]
[BEGIN PAGE TWO]
[diagram]
Lawrence-Klee A4 (nonplanar) graph
[stamped, Mar 18 1976]
26 nodes
how about putting it in Congen to prove it is A4 (and verify the program again)
Josh
Metadata Last Modified Date:
2006-11-29
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