Projective symplectic group over a finite field ($PS{p}_{2m}(q)=S{p}_{2m}(q)/Z$)

The scalar center has order $\gcd (2,q-1)$. The quotient is simple except at $(m,q)=(1,2),(1,3),(2,2)$. The last exception is $S{p}_4(2)\cong S_6$.