A spectral characterization of the s-clique extension of the square grid graphs

Sakander Hayat, Jack H. Koolen, Muhammad Riaz

In this paper we show that for integers $s\ge 2$, $t\ge 1$, any co-edge-regular graph which is cospectral with the $s$-clique extension of the $t\times t$-grid is the $s$-clique ex…