In geometry, the truncated infinite-order square tiling is a uniform tiling of the hyperbolic plane. It has Schläfli symbol of t.
In (*∞44) symmetry this tiling has 3 colors. Bisecting the isosceles triangle domains can double the symmetry to
The dual of the tiling represents the fundamental domains of (*∞44) orbifold symmetry. From [(∞,4,4)] (*∞44) symmetry, there are 15 small index subgroup (11 unique) by mirror removal and alternation operators. Mirrors can be removed if its branch orders are all even, and cuts neighboring branch orders in half. Removing two mirrors leaves a half-order gyration point where the removed mirrors met. In these images fundamental domains are alternately colored black and white, and mirrors exist on the boundaries between colors. The symmetry can be doubled to
| Fundamental domains | valign=top | ||||||
|---|---|---|---|---|---|---|---|
| Subgroup index | 1 | 2 | 4 | ||||
| Coxeter (orbifold) | [(4,4,∞)] (*∞44) | [(1<sup>+</sup>,4,4,∞)] (
| [(4,4,1<sup>+</sup>,∞)] (*∞424) | [(4,1<sup>+</sup>,4,∞)] (
| [(4,1<sup>+</sup>,4,1<sup>+</sup>,∞)] 2*∞2∞2 | [(1<sup>+</sup>,4,4,1<sup>+</sup>,∞)] (∞*2222) | |
| [(4,4<sup>+</sup>,∞)] (4*∞2) | [(4<sup>+</sup>,4,∞)] (4*∞2) | [(4,4,∞<sup>+</sup>)] (∞*22) | [(1<sup>+</sup>,4,1<sup>+</sup>,4,∞)] 2*∞2∞2 | [(4<sup>+</sup>,4<sup>+</sup>,∞)] (∞22×) | |||
| Rotational subgroups | |||||||
| Subgroup index | 2 | 4 | 8 | ||||
| Coxeter (orbifold) | [(4,4,∞)]+ (∞44) | [(1<sup>+</sup>,4,4<sup>+</sup>,∞)] (∞323) | [(4<sup>+</sup>,4,1<sup>+</sup>,∞)] (∞424) | [(4,1<sup>+</sup>,4,∞<sup>+</sup>)] (∞434) | [(1<sup>+</sup>,4,1<sup>+</sup>,4,1<sup>+</sup>,∞)] = [(4<sup>+</sup>,4<sup>+</sup>,∞<sup>+</sup>)] (∞22∞22) | ||