As abstract polytope sidthixhi is isomorphic to gidthixhi, thereby replacing decagons by decagrams and pentagrams by pentagons, respectively replacing gissid by doe and sidditdid by gidditdid. – It also is isomorphic to gixhihy, thereby replacing only decagons by decagrams, respectively replacing sidditdid by gaddid. – Finally it is isomorphic to sixhihy, thereby replacing only pentagrams by pentagons, respectively replacing gissid by doe and sidditdid by saddid. – As such sidthixhi is a lieutenant.

Incidence matrix according to Dynkin symbol

```o3o3x5x5/3*b

. . . .      | 2400 |    3    3 |    3    3   3 |   1   3   1
-------------+------+-----------+---------------+------------
. . x .      |    2 | 3600    * |    2    0   1 |   1   0   2
. . . x      |    2 |    * 3600 |    0    2   1 |   0   1   2
-------------+------+-----------+---------------+------------
. o3x .      |    3 |    3    0 | 2400    *   * |   1   0   1
. o . x5/3*b |    5 |    0    5 |    * 1440   * |   0   1   1
. . x5x      |   10 |    5    5 |    *    * 720 |   0   0   2
-------------+------+-----------+---------------+------------
o3o3x .      ♦    4 |    6    0 |    4    0   0 | 600   *   *
o3o . x5/3*b ♦   20 |    0   30 |    0   12   0 |   * 120   *
. o3x5x5/3*b ♦   60 |   60   60 |   20   12  12 |   *   * 120
```

```o3o3/2x5x5/2*b

. .   . .      | 2400 |    3    3 |    3    3   3 |   1   3   1
---------------+------+-----------+---------------+------------
. .   x .      |    2 | 3600    * |    2    0   1 |   1   0   2
. .   . x      |    2 |    * 3600 |    0    2   1 |   0   1   2
---------------+------+-----------+---------------+------------
. o3/2x .      |    3 |    3    0 | 2400    *   * |   1   0   1
. o   . x5/2*b |    5 |    0    5 |    * 1440   * |   0   1   1
. .   x5x      |   10 |    5    5 |    *    * 720 |   0   0   2
---------------+------+-----------+---------------+------------
o3o3/2x .      ♦    4 |    6    0 |    4    0   0 | 600   *   *
o3o   . x5/2*b ♦   20 |    0   30 |    0   12   0 |   * 120   *
. o3/2x5x5/2*b ♦   60 |   60   60 |   20   12  12 |   *   * 120
```

```o3/2o3x5x5/3*b

.   . . .      | 2400 |    3    3 |    3    3   3 |   1   3   1
---------------+------+-----------+---------------+------------
.   . x .      |    2 | 3600    * |    2    0   1 |   1   0   2
.   . . x      |    2 |    * 3600 |    0    2   1 |   0   1   2
---------------+------+-----------+---------------+------------
.   o3x .      |    3 |    3    0 | 2400    *   * |   1   0   1
.   o . x5/3*b |    5 |    0    5 |    * 1440   * |   0   1   1
.   . x5x      |   10 |    5    5 |    *    * 720 |   0   0   2
---------------+------+-----------+---------------+------------
o3/2o3x .      ♦    4 |    6    0 |    4    0   0 | 600   *   *
o3/2o . x5/3*b ♦   20 |    0   30 |    0   12   0 |   * 120   *
.   o3x5x5/3*b ♦   60 |   60   60 |   20   12  12 |   *   * 120
```

```o3/2o3/2x5x5/2*b

.   .   . .      | 2400 |    3    3 |    3    3   3 |   1   3   1
-----------------+------+-----------+---------------+------------
.   .   x .      |    2 | 3600    * |    2    0   1 |   1   0   2
.   .   . x      |    2 |    * 3600 |    0    2   1 |   0   1   2
-----------------+------+-----------+---------------+------------
.   o3/2x .      |    3 |    3    0 | 2400    *   * |   1   0   1
.   o   . x5/2*b |    5 |    0    5 |    * 1440   * |   0   1   1
.   .   x5x      |   10 |    5    5 |    *    * 720 |   0   0   2
-----------------+------+-----------+---------------+------------
o3/2o3/2x .      ♦    4 |    6    0 |    4    0   0 | 600   *   *
o3/2o   . x5/2*b ♦   20 |    0   30 |    0   12   0 |   * 120   *
.   o3/2x5x5/2*b ♦   60 |   60   60 |   20   12  12 |   *   * 120
```