// Cells and their vertices.
#0={0}
#1={4}
#2={1,7,10}
#3={2,8}
#4={3,6,11}
#5={5,9}
#6={12,17}
#7={13,15,18}
#8={14,16,19}
#9={20}

// Induced graph on cells.
#0:.
#1:.
#2:->#0,#1.
#3:->#0.
#4:->#0,#1.
#5:->#1.
#6:->#2,#4.
#7:->#2,#3,#4,#6.
#8:->#2,#4,#5,#6.
#9:->#6,#7,#8.

// Individual cells.
// cell #0:
0[0]: {}

// cell #1:
0[4]: {}

// cell #2:
0[1]: {2} --> 1,2
1[7]: {3} --> 0
2[10]: {1} --> 0

// cell #3:
0[2]: {1,3} --> 1
1[8]: {2} --> 0

// cell #4:
0[3]: {2} --> 1,2
1[6]: {3} --> 0
2[11]: {1} --> 0

// cell #5:
0[5]: {1,3} --> 1
1[9]: {2} --> 0

// cell #6:
0[12]: {1,3} --> 1
1[17]: {2} --> 0

// cell #7:
0[13]: {2,3} --> 2
1[15]: {1,2} --> 2
2[18]: {1,3} --> 0,1

// cell #8:
0[14]: {2,3} --> 2
1[16]: {1,2} --> 2
2[19]: {1,3} --> 0,1

// cell #9:
0[20]: {1,2,3}