Also True for {$T'$} Claim:Let {$P^1$} and {$P^3$} be paths on {$T'=\langle a_{_T},b_{_T},c_{_T}\rangle$} corresponding to {$L_1$} and {$L_3$}. Then
Proof: For the path of length {$L_1=L_2=a_{_T}+b_{_T}$}, the path vector is {$(2,1,1)$}. For the path of length {$L_3=b_{_T}$} the path vector is {$(0,1,1)$}. So {$$\begin{array}{rcl}\text{GCD}_{_T}\cdot(p^1_a,p^2_a+p^3_a) &=&(b_{_T}-a_{_T},a_{_T})\cdot(2,2)\\ &=&2b_{_T}\end{array}$$} and {$$\begin{array}{rcl}\text{GCD}_{_T}\cdot(p^1_b,p^2_b+p^3_b) &=&(b_{_T}-a_{_T},a_{_T})\cdot(1,2)\\ &=&a_{_T}+b_{_T}\end{array}$$} and {$$\begin{array}{rcl}\text{GCD}_{_T}\cdot(p^1_c,p^2_c+p^3_c) &=&(b_{_T}-a_{_T},a_{_T})\cdot(1,2)\\ &=&a_{_T}+b_{_T},\end{array}$$} and the statements are established for {$T'=\langle a_{_T},b_{_T},c_{_T}\rangle$}. |