$$\pmatrix{
1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \cr
0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \cr
0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 \cr
p_{01,00} & p_{01,11} & 0 & p_{01,01} & 0 & p_{01,10} & 0 & 0 & 0 \cr
p_{02,00} & p_{02,11} & p_{02,22} & p_{02,01} & p_{02,02} & p_{02,10} & p_{02,12} & p_{02,20} & p_{02,21} \cr
p_{10,00} & p_{10,11} & 0 & p_{10,01} & 0 & p_{10,10} & 0 & 0 & 0 \cr
0 & p_{12,11} & p_{12,22} & 0 & 0 & 0 & p_{12,12} & 0 & p_{12,21} \cr
p_{20,00} & p_{20,11} & p_{20,22} & p_{20,01} & p_{20,02} & p_{20,10} & p_{20,12} & p_{20,20} & p_{20,21} \cr
0 & p_{21,11} & p_{21,22} & 0 & 0 & 0 & p_{21,12} & 0 & p_{21,21}
}$$
\bye
