Acronym etripy, J7 Name elongated triangular pyramid ` © ©` Vertex figure [33], [32,42], [3,42] General of army (is itself convex) Colonel of regiment (is itself locally convex) Dihedral angles between {3} and {4} (at tet,trip-join):   arccos[-sqrt(8)/3] = 160.528779° between {3} and {4} (at bottom):   90° between {3} and {3}:   arccos(1/3) = 70.528779° between {4} and {4}:   60° Confer uniform relative: tet   trip   related Johnson solids: etidpy   autip   general polytopal classes: Johnson solids   bistratic lace towers Externallinks

While in etripy the trigonal base of trip gets augmented with a pyramid (tet), autip similarily would have the lacing square being augmented with a pyramid (squippy).

Incidence matrix according to Dynkin symbol

```oxx3ooo&#xt   → height(1,2) = sqrt(3/8) = 0.612372
height(2,3) = 1
(pt || pseudo {3} || {3})

o..3o..    | 1 * * | 3 0 0 0 | 3 0 0
.o.3.o.    | * 3 * | 1 2 1 0 | 2 2 0
..o3..o    | * * 3 | 0 0 1 2 | 0 2 1
-----------+-------+---------+------
oo.3oo.&#x | 1 1 0 | 3 * * * | 2 0 0
.x. ...    | 0 2 0 | * 3 * * | 1 1 0
.oo3.oo&#x | 0 1 1 | * * 3 * | 0 2 0
..x ...    | 0 0 2 | * * * 3 | 0 1 1
-----------+-------+---------+------
ox. ...&#x | 1 2 0 | 2 1 0 0 | 3 * *
.xx ...&#x | 0 2 2 | 0 1 2 1 | * 3 *
..x3..o    | 0 0 3 | 0 0 0 3 | * * 1
```