theorem TBALemma: :: LATTBA_1:19
for T being non empty TBAStruct st ( for v4, v3, v2, v1, v0 being Element of T holds Tern ((Tern (v0,v1,v2)),v3,(Tern (v0,v1,v4))) = Tern (v0,v1,(Tern (v2,v3,v4))) ) & ( for v1, v0 being Element of T holds Tern (v0,v1,v1) = v1 ) & ( for v1, v0 being Element of T holds Tern (v0,v1,(v1 `)) = v0 ) & ( for v1, v0 being Element of T holds Tern (v0,v0,v1) = v0 ) holds
for x, y, z, u, v, v6, w being Element of T holds Tern ((Tern (x,(x `),y)),((Tern ((Tern (z,u,v)),w,(Tern (z,u,v6)))) `),(Tern (u,(Tern (v6,w,v)),z))) = y