I get what you mean, that one might be out of my depth

For example, if you put 6 into the formula it gives you 15 which is:

1v6 2v5 3v4
1v6 2v4 3v5
1v6 2v3 4v5
1v5 2v6 3v4
1v5 2v4 3v6
1v5 2v3 4v6
1v4 2v5 3v6
1v4 2v6 3v5
1v4 2v3 6v5
1v3 2v6 5v4
1v3 2v4 5v6
1v3 2v5 4v6
1v2 3v4 5v6
1v2 3v6 5v4
1v2 3v5 6v4

The formula should represent how many ways you can arrange a full set of matches without caring about order

Not a math expert but I think the formula for this is: x! / ((x/2)!*2^(x/2))

so 8 entrants should give you 105 permutations