Аннотация:
Let $\Gamma$ be a distance-regular graph of diameter 3 with strongly regular graphs $\Gamma_2$ and $\Gamma_3$. Then $\Gamma$ has intersection array $\{t(c_2+1)+a_3,tc_2,a_3+1;1,c_2,t(c_2+1)\}$ (Nirova M.S.) If $\Gamma$ is $Q$-polynomial then either $a_3=0,t=1$ and $\Gamma$ is Taylor graph or $(c_2+1)=a_3(a_3+1)/(t^2-a_3-1)$. We found 4 infinite series feasible intersection arrays in this situation.