Haemers rank bound
= Haemers rank bound
{c}
{title2=$c(G)\leq\operatorname{rank}_F A$}
A fitting matrix over a field has nonzero diagonal entries and zero entries at distinct nonadjacent vertices. Its tensor powers fit strong graph powers. On an independent set the restricted matrix is diagonal and nonsingular, so its cardinality is at most the matrix rank. This yields the capacity upper bound over every field.