To Corresponding Member of USSR AS A.P. Ershov

Novosibirsk

Dear Andrei Petrovich!

Thank you for invitation to the Urgench Symposium. I should be glad to participate if I didn’t
realize that our LOMI group would be much better presented at such unique a symposium by
Anatol’ Slisenko – the author of a world famous theorem on real-time recognizability of symmetric
words (now extended by a number of very interesting result of similar wording).

He made a good name internationally in the area of computation complexity, is in regular
correspondence with the most distinguished foreign specialist in this field, but yet had not a chance
to become acquainted with them in person. For him such an acquaintance would be of great benefit;
I have no doubt that it would be useful for the foreign colleagues as well. It is he and
Yu.V.Matiiasevich (whose name is not in the new list and I can not learn why since he is on
vacation) who can get valuable information for our LOMI group in the best way. Therefore I ask
you to hand over my invitation to A.O. Slisenko.

What for my considerations on symposium program, I should like to draw attention to a prominent
(but not reflected in the symposium data I have received) role of algorithm in semantics of extensive
quantified mathematical languages (for example, arithmetic languages). Semantics of such
languages seems to me to be a rather critical point in mathematics, and confrontation of existing
approaches and points of view with participation of S.C. Kleene, the author of one of fundamental
approaches, could make up a fruitful current of the symposium.

With respect,  N.A. Shanin 

16.07.1979