reserve X for set, x,y,z for object,
  k,l,n for Nat,
  r for Real;
reserve i,i0,i1,i2,i3,i4,i5,i8,i9,j for Integer;
reserve r1,p,p1,g,g1,g2 for Real,
  Y for Subset of REAL;
reserve r, s for Real;
reserve i for Integer,
  a, b, r, s for Real;

theorem Th68:
  a >= [\r/]+1 & a <= r+1 implies [\a/] = [\r/]+1
proof
  assume
A1: a >= [\r/]+1;
  assume a <= r+1;
  then a-1 <= r+1-1 by XREAL_1:9;
  then a-1 < [\r/]+1 by Th29,XXREAL_0:2;
  hence thesis by A1,Def6;
end;
