r = (IntegerNumber) ((Division) rhs).lhs();
rrest = new Division(Naturals.one(), ((Division) rhs).rhs());
}
if (l != null && r != null) {
IntegerNumber lcm = (IntegerNumber) new Lcm(l, r).evaluate();
IntegerNumber gcd = (IntegerNumber) l.multiply(r).divide(lcm);
if (!gcd.isOne()) {
return new Multiplication(gcd, new Addition(
new Multiplication(l.divide(gcd), lrest),