 For a permutation with "n" elements, the maximum number of neighbor exchanging = formula_1

In the same way, the maximum number of legs in a prime with "n" tracks = formula_1

For an arbitrary Ghost Leg, it is possible to transform it into prime by a procedure called bubblization.When bubblization operates, the following two identities are repeatedly applied in order to move and eliminate "useless" legs.When the two identities cannot be applied any more, the ghost leg is proven to be exactly the same as the Ghost Leg constructed by bubble sort, thus bubblization can reduce Ghost Legs to primes.