Demiregular tiling
In geometry, the demiregular tilings are a set of Euclidean tessellations made from 2 or more regular polygon faces. Different authors have listed different sets of tilings. A more systematic approach looking at symmetry orbits are the 2-uniform tilings of which there are 20. Some of the demiregular ones are actually 3-uniform tilings.
20 2-uniform tilings
Grünbaum and Shephard enumerated the full list of 20 2-uniform tilings in Tilings and patterns, 1987:| cmm, 2*22 1 | cmm, 2*22 2 | pmm, *2222 1 | cmm, 2*22 2 | cmm, 2*22 2 | pmm, *2222 1 | pmm, *2222 |
| p4m, *442 | p4g, 4*2 1 | pgg, 2× 2 | p6m, *632 | p6m, *632 1 | p6, 632 2 | cmm, 2*22 |
| p6m, *632 | p6m, *632 | p6m, *632 | p6m, *632 | p6m, *632 | p6m, *632 | - |
Ghyka's list (1946)
Ghyka lists 10 of them with 2 or 3 vertex types, calling them semiregular polymorph partitions.| Plate XXVII No. 12 4.6.12 3.4.6.4 | No. 13 3.4.6.4 3.3.3.4.4 | No. 13 bis. 3.4.4.6 3.3.4.3.4 | No. 13 ter. 3.4.4.6 3.3.3.4.4 | Plate XXIV No. 13 quatuor. 3.4.6.4 3.3.4.3.4 |
| No. 14 33.42 36 | Plate XXVI No. 14 bis. 3.3.4.3.4 3.3.3.4.4 36 | No. 14 ter. 33.42 36 | No. 15 3.3.4.12 36 | Plate XXV No. 16 3.3.4.12 3.3.4.3.4 36 |
Steinhaus's list (1969)
Steinhaus gives 5 examples of non-homogeneous tessellations of regular polygons beyond the 11 regular and semiregular ones.Critchlow's list (1970)
Critchlow identifies 14 demi-regular tessellations, with 7 being 2-uniform, and 7 being 3-uniform.He codes letter names for the vertex types, with superscripts to distinguish face orders. He recognizes A, B, C, D, F, and J can't be a part of continuous coverings of the whole plane.
| A | B | C | D | E | F | G | H | J | K | - |
3.7.42 | 3.8.24 | 3.9.18 | 3.10.15 | 3.12.12 | 4.5.20 | 4.6.12 | 4.8.8 | 5.5.10 | 63 | - |
| L1 | L2 | M1 | M2 | N1 | N2 | P | Q1 | Q2 | R | S |
3.3.4.12 | 3.4.3.12 | 3.3.6.6 | 3.6.3.6 | 3.4.4.6 | 3.4.6.4 | 44 | 3.3.4.3.4 | elongated [triangular tiling|3.3.3.4.4] | 3.3.3.3.6 | 36 |
| 1 | 2 | 4 | 6 | 7 | 10 | 14 |
| E+L2 | L1+ | N1+G | M1+M2 | N2+Q1 | Q1+ | N1+Q2 |