已知函数 f(x)={x2+2x+3,x≤0lnx,x>0f\left( x\right) = \left\{ \begin{array}{l} {x}^{2} + {2x} + 3,x \leq 0 \\ \ln x,x > 0 \end{array}\right.f(x)={x2+2x+3,x≤0lnx,x>0 ,若存在实数 x1,x2,x3{x}_{1},{x}_{2},{x}_{3}x1,x2,x3 且 x1<x2<x3{x}_{1} < {x}_{2} < {x}_{3}x1<x2<x3 ,使得 f(x1)=f(x2)=f(x3)=af\left( {x}_{1}\right) = f\left( {x}_{2}\right) = f\left( {x}_{3}\right) = af(x1)=f(x2)=f(x3)=a ,则 x3(x1+x2+lnx3){x}_{3}\left( {{x}_{1} + {x}_{2} + \ln {x}_{3}}\right)x3(x1+x2+lnx3) 的最大值为___.