theorem Th35:
  a #Z 1 = a
proof
  thus a #Z 1 = a |^ |.1.| by Def3
    .= a |^ (0+1) by ABSVALUE:def 1
    .= a GeoSeq.(0+1) by Def1
    .= a GeoSeq.0 * a by Th3
    .= 1*a by Th3
    .= a;
end;
