Incidence matrix according to symbol extension

x3x:s3s5s = trunc( x3o:s3s5s )   (N → ∞)

60N |   1   1   2   2 |   3   2   1   3   1 |   4 1 1
----+-----------------+---------------------+--------
  2 | 30N   *   *   * |   3   2   0   0   0 |   4 1 0  parts of old edges
  2 |   * 30N   *   * |   1   0   2   0   0 |   2 0 1  underneath tips of former lacing trigs of 3pyrs
  2 |   *   * 60N   * |   1   0   0   2   0 |   2 0 1  underneath base-vertex of former lacing trigs of 3pyrs
  2 |   *   *   * 60N |   0   1   0   1   1 |   1 1 1  underneath vertices of other trigs
----+-----------------+---------------------+--------
  6 |   3   1   2   0 | 30N   *   *   *   * |   2 0 0  trunc of former lacing trigs of 3pyrs
  6 |   3   0   0   3 |   * 20N   *   *   * |   1 1 0  trunc of former other trigs
  3 |   0   3   0   0 |   *   * 20N   *   * |   1 0 1  underneath tip of former 3-pyr
  3 |   0   0   2   1 |   *   *   * 60N   * |   1 0 1  underneath base-vertex of former 3-pyr
  5 |   0   0   0   5 |   *   *   *   * 12N |   0 1 1  underneath vertex of former ike
----+-----------------+---------------------+--------
 12 |   6   3   6   3 |   3   1   1   3   0 | 20N * *  tut
 60 |  30   0   0  60 |   0  20   0   0  12 |   * N *  ti
 60 |   0  30  60  60 |   0   0  20  60  12 |   * * N  snid