protected override int Descendant(int i, int index, int branch)
{
int modulo = Tree1.Count(i);
int index1 = index % modulo;
int index2 = index / modulo;
int branch1 = branch % 3;
int branch2 = branch / 3;
modulo = Tree1.Count(i + 1);
return(Tree1.Descendant(i, index1, branch1) +
Tree2.Descendant(i, index2, branch2) * modulo);
}