Incidence matrix according to Dynkin symbol

s∞o2s4o4x   (N → ∞)

demi( . . . . . ) | 4N |  2  4  1 | 1  6  4 |  2 4
------------------+----+----------+---------+-----
demi( . . . . x ) |  2 | 4N  *  * | 1  0  2 |  0 3
      s 2 s . .   |  2 |  * 8N  * | 0  2  1 |  1 2
      . . s4o .   |  2 |  *  * 2N | 0  4  0 |  2 2
------------------+----+----------+---------+-----
demi( . . . o4x ) |  4 |  4  0  0 | N  *  * |  0 2
sefa( s 2 s4o . ) |  3 |  0  2  1 | * 8N  * |  1 1
sefa( s 2 s 2 x ) |  4 |  2  2  0 | *  * 4N |  0 2
------------------+----+----------+---------+-----
      s 2 s4o .   ♦  4 |  0  4  2 | 0  4  0 | 2N *
sefa( s∞o2s4o4x ) ♦ 16 | 12 16  4 | 2  8  8 |  * N

starting figure: x∞o x4o4x