# D1 = readDom["{j,N | 0<=j<=N-1; 2<=N}"]
D 1
4 4
1   1  0   0
1  -1  1  -1
1   0  1  -2
1   0  0   1
# D2 = readDom["{j, N | 1<=j<=N; 2<=N}"]
D 1
4 4
1  1  0  -1
1 -1  1   0
1  0  1  -2
1  0  0   1
F 1
# D12 = DomConvex[DomUnion[D1,D2]]
# ashow[D12] = {j,N | 0<=j<=N; 2<=N}
