The Ehrenfeucht-fra¨ıssé-game of Length Ω 1

نویسندگان

  • Alan Mekler
  • Saharon Shelah
  • Jouko Väänänen
چکیده

Let A and B be two first order structures of the same vocabulary. We shall consider the Ehrenfeucht-Fräıssé-game of length ω1 of A and B which we denote by Gω1(A,B). This game is like the ordinary Ehrenfeucht-Fräıssé-game of Lωω except that there are ω1 moves. It is clear that Gω1(A,B) is determined if A and B are of cardinality ≤ א1. We prove the following results:

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تاریخ انتشار 1993