ABSTRACT
Let’s designate the racers by their first initials as {A,B,C,D}, with the following possible orders:
{A,B,C,D},{A,B,D,C},{A,C,B,D},{A,C,D,B},{A,D,B,C},{A,D,C,B}, {B,A,C,D},{B,A,D,C},{B,C,A,D},{B,C,D,A},{B,D,A,C},{B,D,C,A}, {C,A,B,D},{C,A,D,B},{C,B,A,D},{C,B,D,A},{C,D,A,B},{C,D,B,A}, {D,A,B,C},{D,A,C,B},{D,B,A,C},{D,B,C,A},{D,C,A,B},{D,C,B,A}.
