:: Go-Board Theorem
:: by Jaros{\l}aw Kotowicz and Yatsuka Nakamura
::
:: Received August 24, 1992
:: Copyright (c) 1992 Association of Mizar Users
theorem Th1: :: GOBOARD4:1
theorem Th2: :: GOBOARD4:2
theorem :: GOBOARD4:3
:: deftheorem Def1 defines lies_between GOBOARD4:def 1 :
:: deftheorem Def2 defines lies_between GOBOARD4:def 2 :
theorem Th4: :: GOBOARD4:4
theorem Th5: :: GOBOARD4:5
theorem :: GOBOARD4:6
canceled;
theorem :: GOBOARD4:7
canceled;
theorem :: GOBOARD4:8