Distance-regular graphs with intersection array $\{69,56,10;1,14,60\}$, $\{74,54,15;1,9,60\}$ and $\{119,100,15;1,20,105\}$ do not exist

Distance regular graphs $\Gamma$ of diameter 3 for which the graphs $\Gamma_2$ and $\Gamma_3$ are strongly regular, studied by M.S. Nirova. For $Q$-polynomial graphs with intersection arrays $\{69,56,10; 1,14,60\}$ and $\{119,100,15; 1, 20,105\}$ the graph $\Gamma_3$ is strongly regular and does not contain triangles. Automorphisms of graphs with these intersection arrays were found by A.A. Makhnev, M.S. Nirova and M.M. Isakova, A.A. Makhnev, respectively. The graph $\Gamma$ with the intersection array $\{74,54,15; 1,9,60\} $ also is $Q $-polynomial, and $\Gamma_3$ is a strongly regular graph with parameters $(630,111,12,21)$. It is proved in the paper that graphs with intersection arrays $\{69,56,10;1,14,60\}$, $\{74,54,15; 1,9,60\}$ and $\{119,100,15; 1,20, 105\} $ do not exist.