A type of model first introduced by Linus Pauling to explain partiallycooperative ligand binding is the sequential model. Here we consider two sequential binding models.See pp $185-186$ Tinoco $5$th edition for reference. Note the notation used in the text is a little different than the notation that we use in the notes. On pp$185-186$ S$=$k$[$L$]$ and $\backslash$tau $=$f$.$