Incidence matrix according to symbol extension

x3x:s3s6s = trunc( x3o:s3s6s )   (N,M → ∞)

6NM |   1   1   2   2 |   3   2   1   3  1 |   4 1 1
----+-----------------+--------------------+--------
  2 | 3NM   *   *   * |   3   2   0   0  0 |   4 1 0  parts of old edges
  2 |   * 3NM   *   * |   1   0   2   0  0 |   2 0 1  underneath tips of former lacing trigs of 3pyrs
  2 |   *   * 6NM   * |   1   0   0   2  0 |   2 0 1  underneath base-vertex of former lacing trigs of 3pyrs
  2 |   *   *   * 6NM |   0   1   0   1  1 |   1 1 1  underneath vertices of other trigs
----+-----------------+--------------------+--------
  6 |   3   1   2   0 | 3NM   *   *   *  * |   2 0 0  trunc of former lacing trigs of 3pyrs
  6 |   3   0   0   3 |   * 2NM   *   *  * |   1 1 0  trunc of former other trigs
  3 |   0   3   0   0 |   *   * 2NM   *  * |   1 0 1  underneath tip of former 3-pyr
  3 |   0   0   2   1 |   *   *   * 6NM  * |   1 0 1  underneath base-vertex of former 3-pyr
  6 |   0   0   0   6 |   *   *   *   * NM |   0 1 1  underneath vertex of former trat
----+-----------------+--------------------+--------
 12 |   6   3   6   3 |   3   1   1   3  0 | 2NM * *  tut
 6M |  3M   0   0  6M |   0  2M   0   0  M |   * N *  hexat
 6M |   0  3M  6M  6M |   0   0  2M  6M  M |   * * N  snathat