....¹

This was not cited in the original article, and I do not know how this formula is derived. However, knowing the origin of this formula is not crucial to understanding the rest of his proof, and so I accepted his word that it was valid.

.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.