  We use the notation ‘\(\Diamond^n\)’ to represent \(n\) diamonds in a row, so, for example, ‘\(\Diamond^3\)’ abbreviates a string of three diamonds: ‘\(\Diamond \Diamond \Diamond\)’. Similarly ‘\(\Box^n\)’ represents a string of \(n\) boxes. When the values of \(h, i, j\), and \(k\) are all 1, we have axiom \((C)\):