SEP 95 1963

MASSACHUSETTS INSTITUTE OF TECHNOLOGY

CAMBRIDGE 39, MASSACHUSETTS

September 4, 1963

Prof. Joshua Lederberg
Department of Genetics
Stanford Medical Center
Palo Alto, California

Dear Josh:

I don't know a name for your series. But you could call it "Hanoi".

For it is precisely the order in which pieces are moved to solve the
pyramid puzzle,

called "Tower of Hanoi".

KNS VI YW

The solution, your series, is essentially unique, except for back-

tracking. I don't know anything about your generating process,
which might be represented as

Hn _ .
2 - l= (n) ,KOR(n 1),

or Hn = log[(R)XOR(n - 1) + 1]

Sincerely,

~
t

afar "9 ma Wauw-m

pe Marvin Minsky

7 ny MM: cs ae :

YY manana, ny pee ark
ae? =a a _— pn a

umes a

B

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