Strongly regular graphs

Mathematics · Graph theory Brouwer’s graph tables

Existence of directed strongly regular graphs with parameters (57,22,14,9,8) and (93,34,18,13,12)

We prove the existence of directed strongly regular graphs (dsrgs) with parameters $(57,22,14,9,8)$ and $(93,34,18,13,12)$, and hence also of their complements

Existence of DSRGs (32+8s,14+4s,7+2s,5+2s,7+2s) and (108+27s,33+9s,11+3s,8+3s,11+3s)

We construct directed strongly regular graphs with parameters $(4r,2r-2,r-1,r-3,r-1)$ for every even integer $r\geq8$, and a second family with parameters $(108