13,3)=(133-13)/9=120/9=40/3
(100a+10b+c-10a-b)/90+(100b+10c+a-10b-c)/90+(100c+10a+b-10c-a)/90 = =40/3
(90a+9b+c)/90+(90b+9c+a)/90+(90c+9a+b)/90 = 40/3
90a+9b+c+90b+9c+a+90c+9a+b =1200
100a+100b+100c =1200
100(a+b+c) =1200
a+b+c=12
a+c=5b
5b+b=12
6b=12
b=2
a+c=10
a={1,2,3,4,5,6,7,8,9}
c={9,8,7,6,5,4,3,2,1}