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␈β↓Q␈↓ ¬	STANFORD UNIVERSITY
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␈↓β␈↓ ¬_STANFORD, CALIFORNIA 94305
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␈↓∧
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␈↓ ↓H

␈↓ ↓H

␈↓ ↓H
ARTIFICIAL INTELLIGENCE LABORATORY␈↓ 
+   Telephone:
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COMPUTER SCIENCE DEPARTMENT␈↓ 
+415-497-4430
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␈↓␈↓ ¬k15 January 1975
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␈↓ ↓H

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␈↓ ↓H
Professor Andrei Ershov
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Computing Center
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Novosibirsk 630090
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U.S.S.R.
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Dear Andrei:
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␈↓ ↓H
␈↓ α_I␈α∀had␈α∀been␈α∀looking␈α∀forward␈α∀to␈α∀seeing␈α∀you␈α∀at␈α∪the␈α∪conference␈α∪in␈α∪Los␈α∪Angeles␈α∪in␈α∪April.
␈↓ ↓H
␈↓ ↓HUnfortunately␈αfor␈αthat,␈αthough␈αfortunately␈αfor␈αother␈αreasons,␈αI␈αwill␈αbe␈αin␈αJapan␈αat␈αKyoto␈αUniversity
␈↓ ↓H
␈↓ ↓Hbetween␈αMarch␈α25␈αand␈αJune␈α30.␈αHowever,␈αI␈αhope␈αyou␈αwill␈αbe␈αable␈αto␈αvisit␈αStanford␈αanyway,␈αand␈αif
␈↓ ↓H
␈↓ ↓Hyour␈α
other␈α
friends␈α
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haven't␈α
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to␈α
arrange␈α
it,␈α
I␈α
will␈α
be␈α
glad␈α
to␈α
help.
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␈↓ α_While␈αthe␈αFoonly␈αproject␈αcollapsed␈αafter␈αthe␈αdesign␈αwas␈αcompleted,␈αit␈αhad␈αthe␈αgood␈αresult␈αthat
␈↓ ↓H
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us␈α
a␈α
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which␈α
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␈↓ ↓H
␈↓ ↓Hthat␈α⊂we␈α⊂are␈α⊂getting␈α⊂256K␈α⊂more␈α⊂memory,␈α⊂keeping␈α⊂the␈α⊂KA-10␈α∂processor,␈α∂and␈α∂building␈α∂a␈α∂mapping
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␈↓ ↓Hmultiplexor␈αto␈αconnect␈αi-o␈αdevices␈αto␈αmemory␈αand␈αto␈αmap␈αthe␈αi-o␈αdevices␈αinto␈αmemory␈αin␈αthe␈αpaging
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␈↓ ↓Henvironment␈α
of␈α
the␈α
PDP-10.
␈↓ ↓H

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␈↓ α_I␈α⊃have␈α⊃been␈α⊃working␈α⊃quite␈α⊃steadily␈α⊃on␈α⊃expressing␈α⊃the␈α⊃Scott␈α⊃logic␈α⊃of␈α⊂continuous␈α⊂functions
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and␈α
am␈α
thinking␈α
that␈α
research␈α
in␈α
pattern
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come␈α
to␈α
Stanford,␈α
you␈α
can
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Richard␈α
Weyhrauch,␈α
Michael␈α
Gordon,␈α
and␈α
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Arthur␈α
Thomas␈α
about␈α
these␈α
ideas.
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for␈α
him;␈α
we␈α
enjoyed␈α
having␈α
him.
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to␈α
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you␈α
in␈α
Tblisi␈α
in␈α
August␈α
and␈α
maybe␈α
in␈α
Novosibirsk␈α
too,␈α
but␈α
I␈α
am␈α
not␈α
yet
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␈↓ ↓H

␈↓ εW
Best Regards,
␈↓ εW

␈↓ εW

␈↓ εW

␈↓ εW

␈↓ εW

␈↓ εW
John McCarthy
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Director, Artificial Intelligence Laboratory
␈↓ εW
Professor of Computer Science
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JMC:pw
␈↓ ↓H
andrei.le4[let,jmc]:SU-AI
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␈↓ ↓H
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a␈α
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and␈α
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intended␈α
to␈α
be␈α
used␈α
as␈α
a␈αvirtual␈αmemory␈αfor␈αan␈αIBM␈α3330,␈αi.e.␈αto␈αmake␈αthe
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␈↓ ↓H3330␈αappear␈αto␈αthe␈αcomputer␈αas␈αthough␈αit␈αwere␈αmuch␈αlarger.␈αIBM␈αalready␈αhas␈αorders␈αfor␈αmore␈αthan
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␈↓ ↓H500␈α∞of␈α∞them.␈α∞This␈α∞makes␈α∞putting␈α∞large␈α∞libraries␈α
on␈α
line␈α
really␈α
feasible␈α
since␈α
storing␈α
a␈α
book␈α
would
␈↓ ↓H
␈↓ ↓Hhave␈α
a␈α
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of␈α
less␈α
than␈α
$5.00␈α
which␈α
is␈αless␈αthan␈αkeeping␈αit␈αon␈αa␈αlibrary␈αshelf,␈αcounting␈αthe
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The␈α
real␈α
problem␈α
now␈α
is␈α
getting␈α
the␈α
books␈α
into␈α
the␈α
computer.
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␈↓ ↓H
␈↓ α_We␈α∞can't␈α∞afford␈α
to␈α
buy␈α
a␈α
3850␈α
by␈α
ourselves,␈α
because␈α
the␈α
cheapest␈α
version␈α
storing␈α
a␈α
mere␈α
35
␈↓ ↓H
␈↓ ↓Hbillion␈αbytes␈αcosts␈αabout␈αa␈αmillion.␈αTherefore,␈αwe␈αare␈αtrying␈αto␈αform␈αa␈αco-op␈αof␈α
local␈α
PDP-10s␈α
to␈α
rent
␈↓ ↓H
␈↓ ↓Hone␈α∞jointly␈α∞and␈α∞connect␈α∞it␈α
to␈α
all␈α
our␈α
computers.␈α
It␈α
is␈α
too␈α
soon␈α
to␈α
say␈α
whether␈α
this␈α
is␈α
technically␈α
or
␈↓ ↓H
␈↓ ↓Hadministratively␈α
feasible.
␈↓ ↓H

␈↓ ↓H