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Failed Archimedeans

Failed Archimedeans

The failed Archimedeans are weird "shapes" (if you can even call them that). By extension from the Archimedean solids, they are uniform (have congruent vertices*) and regular-faced, but cannot otherwise be constructed. They are constructed just like how normal Archimedeans are constructed, by taking a single vertex configuration (i.e. one pentagon and two hexagons for a truncated icosahedron) and extending it. For the failed Archimedeans, this process fails, and constructing them analogously to the Archimedeans leads to places where more than two faces meet an edge and make them dense.

There are still a few restrictions, however:
1. The sum of the internal angles of the polygons making up the vertex configuration must add up to less than 360° (e.g. five squares isn't allowed since the sum of the internal angles is 450°).
2. A single vertex must be constructible (e.g. two triangles and one heptagon isn't allowed since you can't make the triangles meet). Relaxing this restriction makes the pyramidoids (3.3.x), tetrapyramidoids (3.4.x) and pentapyramidoids (3.5.x) infinite families.

The Desmos graph I used to test the formulae an be found here. All the info about these were generated using a Python program. The quadriverticed circumradii were calculating with the circumradius of x3/2x(x)o(y)*a, with (x) and (y) being the polygons in a 3.3.x.y configuration.

Note that the vertex count is simply extrapolated from the usual method of calculating by the fact that summing the missing vertex angles of any convex polyhedron results in 720°. Their actual vertex count is infinite as they are dense.

Failed Archimedeans list (147+∞)

Triverticed (126+∞)

Vert. Conf. Name Vertices Circumradius Dihedral angles
3.3.4 Square pyramidoid 4.8 (4+4/5) 0.70710678 3–3: 109.471°, 3–4: 54.736°, 4–3: 54.736°
3.3.5 Pentagonal pyramidoid 5.455 (5+5/11) 0.95105652 3–3: 138.19°, 3–5: 37.377°, 5–3: 37.377°
3.4.5 Pentagonal tetrapyramidoid 7.059 (7+1/17) 0.8660254 3–4: 110.905°, 4–5: 58.283°, 5–3: 79.188°
3.4.6 Hexagonal tetrapyramidoid 8 1 3–4: 125.264°, 4–6: 54.736°, 6–3: 70.529°
3.4.7 Heptagonal tetrapyramidoid 8.842 (8+16/19) 1.17195981 3–4: 136.05°, 4–7: 50.244°, 7–3: 62.586°
3.4.8 Octagonal tetrapyramidoid 9.6 (9+3/5) 1.39896633 3–4: 144.736°, 4–8: 45°, 8–3: 54.736°
3.4.9 Enneagonal tetrapyramidoid 10.286 (10+2/7) 1.71922572 3–4: 152.196°, 4–9: 38.935°, 9–3: 46.523°
3.4.10 Decagonal tetrapyramidoid 10.909 (10+10/11) 2.23295051 3–4: 159.095°, 4–10: 31.717°, 10–3: 37.377°
3.4.11 Hendecagonal tetrapyramidoid 11.478 (11+11/23) 3.33677158 3–4: 166.263°, 4–11: 22.358°, 11–3: 26.055°
3.5.5 Pentagonal pentapyramidoid 8.571 (8+4/7) 0.95105652 3–5: 100.812°, 5–5: 63.435°, 5–3: 100.812°
3.5.6 Hexagonal pentapyramidoid 10 1.06212772 3–5: 114.801°, 5–6: 65.199°, 6–3: 94.513°
3.5.7 Heptagonal pentapyramidoid 11.351 (11+13/37) 1.18698035 3–5: 124.708°, 5–7: 65.586°, 7–3: 89.769°
3.5.8 Octagonal pentapyramidoid 12.632 (12+12/19) 1.32199705 3–5: 132.138°, 5–8: 65.255°, 8–3: 85.829°
3.5.9 Enneagonal pentapyramidoid 13.846 (13+11/13) 1.4658125 3–5: 137.943°, 5–9: 64.49°, 9–3: 82.36°
3.5.10 Decagonal pentapyramidoid 15 1.61803399 3–5: 142.623°, 5–10: 63.435°, 10–3: 79.188°
3.5.11 Hendecagonal pentapyramidoid 16.098 (16+4/41) 1.77883396 3–5: 146.49°, 5–11: 62.171°, 11–3: 76.209°
3.5.12 Dodecagonal pentapyramidoid 17.143 (17+1/7) 1.94879366 3–5: 149.754°, 5–12: 60.746°, 12–3: 73.36°
3.5.13 Tridecagonal pentapyramidoid 18.14 (18+6/43) 2.1288491 3–5: 152.556°, 5–13: 59.19°, 13–3: 70.596°
3.5.14 Tetradecagonal pentapyramidoid 19.091 (19+1/11) 2.32029289 3–5: 154.998°, 5–14: 57.521°, 14–3: 67.884°
3.5.15 Pentadecagonal pentapyramidoid 20 2.52481765 3–5: 157.156°, 5–15: 55.752°, 15–3: 65.199°
3.5.16 Hexadecagonal pentapyramidoid 20.87 (20+20/23) 2.74460044 3–5: 159.085°, 5–16: 53.887°, 16–3: 62.521°
3.5.17 Heptadecagonal pentapyramidoid 21.702 (21+33/47) 2.98243745 3–5: 160.829°, 5–17: 51.93°, 17–3: 59.831°
3.5.18 Octadecagonal pentapyramidoid 22.5 (22+1/2) 3.24194919 3–5: 162.423°, 5–18: 49.877°, 18–3: 57.113°
3.5.19 Enneadecagonal pentapyramidoid 23.265 (23+13/49) 3.52789245 3–5: 163.893°, 5–19: 47.726°, 19–3: 54.35°
3.5.20 Icosagonal pentapyramidoid 24 3.84664395 3–5: 165.264°, 5–20: 45.468°, 20–3: 51.523°
3.5.21 Icosihenagonal pentapyramidoid 24.706 (24+12/17) 4.20697418 3–5: 166.554°, 5–21: 43.092°, 21–3: 48.612°
3.5.22 Icosidigonal pentapyramidoid 25.385 (25+5/13) 4.62133821 3–5: 167.782°, 5–22: 40.581°, 22–3: 45.593°
3.5.23 Icositrigonal pentapyramidoid 26.038 (26+2/53) 5.10814607 3–5: 168.964°, 5–23: 37.911°, 23–3: 42.436°
3.5.24 Icositetragonal pentapyramidoid 26.667 (26+2/3) 5.69603162 3–5: 170.117°, 5–24: 35.05°, 24–3: 39.1°
3.5.25 Icosipentagonal pentapyramidoid 27.273 (27+3/11) 6.43260236 3–5: 171.26°, 5–25: 31.948°, 25–3: 35.529°
3.5.26 Icosihexagonal pentapyramidoid 27.857 (27+6/7) 7.40456989 3–5: 172.416°, 5–26: 28.531°, 26–3: 31.637°
3.5.27 Icosiheptagonal pentapyramidoid 28.421 (28+8/19) 8.79231879 3–5: 173.619°, 5–27: 24.668°, 27–3: 27.28°
3.5.28 Icosioctagonal pentapyramidoid 28.966 (28+28/29) 11.06106306 3–5: 174.932°, 5–28: 20.108°, 28–3: 22.181°
3.5.29 Icosienneagonal pentapyramidoid 29.492 (29+29/59) 16.05118514 3–5: 176.511°, 5–29: 14.194°, 29–3: 15.621°
3.6.x, x≥7 Hexapyramidoids (infinite family) 2x
3.7.7 Heptagonal heptatruncatoid 16.8 (16+4/5) 1.44012994 3–7: 117.414°, 7–7: 79.513°, 7–3: 117.414°
3.7.8 Octagonal heptatruncatoid 19.765 (19+13/17) 1.59475501 3–7: 125.727°, 7–8: 83.86°, 8–3: 116.155°
3.7.9 Enneagonal heptatruncatoid 22.909 (22+10/11) 1.75890693 3–7: 132.141°, 7–9: 87.448°, 9–3: 115.593°
3.7.10 Decagonal heptatruncatoid 26.25 (26+1/4) 1.93055208 3–7: 137.259°, 7–10: 90.55°, 10–3: 115.479°
3.7.11 Hendecagonal heptatruncatoid 29.806 (29+25/31) 2.10875285 3–7: 141.448°, 7–11: 93.325°, 11–3: 115.676°
3.7.12 Dodecagonal heptatruncatoid 33.6 (33+3/5) 2.29312836 3–7: 144.948°, 7–12: 95.867°, 12–3: 116.097°
3.7.13 Tridecagonal heptatruncatoid 37.655 (37+19/29) 2.48362675 3–7: 147.922°, 7–13: 98.24°, 13–3: 116.689°
3.7.14 Tetradecagonal heptatruncatoid 42 2.68041722 3–7: 150.486°, 7–14: 100.487°, 14–3: 117.414°
3.7.15 Pentadecagonal heptatruncatoid 46.667 (46+2/3) 2.88383632 3–7: 152.724°, 7–15: 102.64°, 15–3: 118.249°
3.7.16 Hexadecagonal heptatruncatoid 51.692 (51+9/13) 3.09436211 3–7: 154.699°, 7–16: 104.721°, 16–3: 119.174°
3.7.17 Heptadecagonal heptatruncatoid 57.12 (57+3/25) 3.31260463 3–7: 156.457°, 7–17: 106.748°, 17–3: 120.176°
3.7.18 Octadecagonal heptatruncatoid 63 3.53930722 3–7: 158.037°, 7–18: 108.735°, 18–3: 121.246°
3.7.19 Enneadecagonal heptatruncatoid 69.391 (69+9/23) 3.77535632 3–7: 159.467°, 7–19: 110.694°, 19–3: 122.378°
3.7.20 Icosagonal heptatruncatoid 76.364 (76+4/11) 4.02179901 3–7: 160.771°, 7–20: 112.633°, 20–3: 123.565°
3.7.21 Icosihenagonal heptatruncatoid 84 4.27986869 3–7: 161.967°, 7–21: 114.561°, 21–3: 124.805°
3.7.22 Icosidigonal heptatruncatoid 92.4 (92+2/5) 4.55102011 3–7: 163.072°, 7–22: 116.486°, 22–3: 126.096°
3.7.23 Icositrigonal heptatruncatoid 101.684 (101+13/19) 4.8369762 3–7: 164.097°, 7–23: 118.413°, 23–3: 127.436°
3.7.24 Icositetragonal heptatruncatoid 112 5.13979018 3–7: 165.054°, 7–24: 120.35°, 24–3: 128.825°
3.7.25 Icosipentagonal heptatruncatoid 123.529 (123+9/17) 5.46192837 3–7: 165.953°, 7–25: 122.302°, 25–3: 130.264°
3.7.26 Icosihexagonal heptatruncatoid 136.5 (136+1/2) 5.80638149 3–7: 166.8°, 7–26: 124.276°, 26–3: 131.755°
3.7.27 Icosiheptagonal heptatruncatoid 151.2 (151+1/5) 6.17681657 3–7: 167.604°, 7–27: 126.277°, 27–3: 133.299°
3.7.28 Icosioctagonal heptatruncatoid 168 6.5777875 3–7: 168.369°, 7–28: 128.314°, 28–3: 134.899°
3.7.29 Icosienneagonal heptatruncatoid 187.385 (187+5/13) 7.01503301 3–7: 169.102°, 7–29: 130.392°, 29–3: 136.561°
3.7.30 Triacontagonal heptatruncatoid 210 7.495908 3–7: 169.808°, 7–30: 132.522°, 30–3: 138.29°
3.7.31 Triacontahenagonal heptatruncatoid 236.727 (236+8/11) 8.03002533 3–7: 170.492°, 7–31: 134.713°, 31–3: 140.092°
3.7.32 Triacontadigonal heptatruncatoid 268.8 (268+4/5) 8.6302409 3–7: 171.159°, 7–32: 136.977°, 32–3: 141.978°
3.7.33 Triacontatrigonal heptatruncatoid 308 9.31422326 3–7: 171.812°, 7–33: 139.328°, 33–3: 143.959°
3.7.34 Triacontatetragonal heptatruncatoid 357 10.10706801 3–7: 172.458°, 7–34: 141.785°, 34–3: 146.05°
3.7.35 Triacontapentagonal heptatruncatoid 420 11.04589451 3–7: 173.102°, 7–35: 144.372°, 35–3: 148.272°
3.7.36 Triacontahexagonal heptatruncatoid 504 12.18849149 3–7: 173.751°, 7–36: 147.122°, 36–3: 150.654°
3.7.37 Triacontaheptagonal heptatruncatoid 621.6 (621+3/5) 13.63104704 3–7: 174.414°, 7–37: 150.081°, 37–3: 153.238°
3.7.38 Triacontaoctagonal heptatruncatoid 798 15.54896593 3–7: 175.105°, 7–38: 153.322°, 38–3: 156.089°
3.7.39 Triacontaenneagonal heptatruncatoid 1092 18.30759585 3–7: 175.844°, 7–39: 156.966°, 39–3: 159.315°
3.7.40 Tetracontagonal heptatruncatoid 1680 22.85040712 3–7: 176.671°, 7–40: 161.248°, 40–3: 163.129°
3.7.41 Tetracontahenagonal heptatruncatoid 3444 32.91508097 3–7: 177.69°, 7–41: 166.779°, 41–3: 168.084°
3.8.9 Enneagonal octatruncatoid 28.8 (28+4/5) 1.98224354 3–8: 132.345°, 8–9: 95.261°, 9–3: 125.604°
3.8.10 Decagonal octatruncatoid 34.286 (34+2/7) 2.20403635 3–8: 138.053°, 8–10: 99.984°, 10–3: 126.474°
3.8.11 Hendecagonal octatruncatoid 40.615 (40+8/13) 2.44531855 3–8: 142.789°, 8–11: 104.367°, 11–3: 127.724°
3.8.12 Dodecagonal octatruncatoid 48 2.70867773 3–8: 146.81°, 8–12: 108.532°, 12–3: 129.271°
3.8.13 Tridecagonal octatruncatoid 56.727 (56+8/11) 2.99813927 3–8: 150.296°, 8–13: 112.568°, 13–3: 131.064°
3.8.14 Tetradecagonal octatruncatoid 67.2 (67+1/5) 3.31947321 3–8: 153.371°, 8–14: 116.539°, 14–3: 133.075°
3.8.15 Pentadecagonal octatruncatoid 80 3.68085205 3–8: 156.13°, 8–15: 120.501°, 15–3: 135.291°
3.8.16 Hexadecagonal octatruncatoid 96 4.09403581 3–8: 158.644°, 8–16: 124.503°, 16–3: 137.711°
3.8.17 Heptadecagonal octatruncatoid 116.571 (116+4/7) 4.57650698 3–8: 160.974°, 8–17: 128.599°, 17–3: 140.348°
3.8.18 Octadecagonal octatruncatoid 144 5.15551555 3–8: 163.169°, 8–18: 132.846°, 18–3: 143.228°
3.8.19 Enneadecagonal octatruncatoid 182.4 (182+2/5) 5.87638774 3–8: 165.276°, 8–19: 137.322°, 19–3: 146.394°
3.8.20 Icosagonal octatruncatoid 240 6.82164699 3–8: 167.348°, 8–20: 142.133°, 20–3: 149.921°
3.8.21 Icosihengonal octatruncatoid 336 8.16282798 3–8: 169.449°, 8–21: 147.454°, 21–3: 153.943°
3.8.22 Icosidigonal octatruncatoid 528 10.34187538 3–8: 171.688°, 8–22: 153.616°, 22–3: 158.725°
3.8.23 Icositrigonal octatruncatoid 1104 15.10507357 3–8: 174.318°, 8–23: 161.47°, 23–3: 164.961°
3.9.9 Enneagonal enneatruncatoid 36 2.24242099 3–9: 133.477°, 9–9: 102.13°, 9–3: 133.477°
3.9.10 Decagonal enneatruncatoid 45 2.54360186 3–9: 139.93°, 9–10: 108.477°, 10–3: 135.254°
3.9.11 Hendecagonal enneatruncatoid 56.571 (56+4/7) 2.89602966 3–9: 145.403°, 9–11: 114.559°, 11–3: 137.54°
3.9.12 Dodecagonal enneatruncatoid 72 3.31766778 3–9: 150.188°, 9–12: 120.561°, 12–3: 140.273°
3.9.13 Tridecagonal enneatruncatoid 93.6 (93+3/5) 3.83952518 3–9: 154.498°, 9–13: 126.647°, 13–3: 143.451°
3.9.14 Tetragonal enneatruncatoid 126 4.51874447 3–9: 158.503°, 9–14: 132.993°, 14–3: 147.119°
3.9.15 Pentagonal enneatruncatoid 180 5.47448714 3–9: 162.369°, 9–15: 139.843°, 15–3: 151.402°
3.9.16 Hexagonal enneatruncatoid 288 7.01374594 3–9: 166.311°, 9–16: 147.618°, 16–3: 156.578°
3.9.17 Heptagonal enneatruncatoid 612 10.34792914 3–9: 170.762°, 9–17: 157.364°, 17–3: 163.402°
3.10.11 Hendecagonal decatruncatoid 82.5 (82+1/2) 3.52549375 3–10: 149.091°, 10–11: 124.63°, 11–3: 146.05°
3.10.12 Dodecagonal decatruncatoid 120 4.30673898 3–10: 155.046°, 10–12: 133.052°, 12–3: 150.267°
3.10.13 Tridecagonal decatruncatoid 195 5.56002905 3–10: 160.877°, 10–13: 142.376°, 13–3: 155.522°
3.10.14 Tetradecagonal decatruncatoid 420 8.26045496 3–10: 167.237°, 10–14: 153.836°, 14–3: 162.586°
3.11.11 Hendecagonal hendecatruncatoid 132 4.50447394 3–11: 153.945°, 11–11: 135.285°, 11–3: 153.945°
3.11.12 Dodecagonal hendecatruncatoid 264 6.43955436 3–11: 162.042°, 11–12: 147.722°, 12–3: 160.526°
3.11.13 Tridecagonal hendecatruncatoid 1716 16.59820836 3–11: 173.112°, 11–13: 167.086°, 13–3: 171.98°
4.5.5 Pentagonal pentagrombatoid 13.333 (13+1/3) 1.14412281 4–5: 108.961°, 5–5: 96.06°, 5–4: 108.961°
4.5.6 Hexagonal pentagrombatoid 17.143 (17+1/7) 1.32287566 4–5: 121.717°, 5–6: 100.812°, 6–4: 110.905°
4.5.7 Heptagonal pentagrombatoid 21.538 (21+7/13) 1.51993462 4–5: 130.963°, 5–7: 105.018°, 7–4: 113.281°
4.5.8 Octagonal pentagrombatoid 26.667 (26+2/3) 1.73555662 4–5: 138.03°, 5–8: 108.961°, 8–4: 115.914°
4.5.9 Enneagonal pentagrombatoid 32.727 (32+8/11) 1.9719251 4–5: 143.655°, 5–9: 112.782°, 9–4: 118.734°
4.5.10 Decagonal pentagrombatoid 40 2.23295051 4–5: 148.283°, 5–10: 116.565°, 10–4: 121.717°
4.5.11 Hendecagonal pentagrombatoid 48.889 (48+8/9) 2.52458442 4–5: 152.196°, 5–11: 120.37°, 11–4: 124.86°
4.5.12 Dodecagonal pentagrombatoid 60 2.85562786 4–5: 155.587°, 5–12: 124.248°, 12–4: 128.173°
4.5.13 Tridecagonal pentagrombatoid 74.286 (74+2/7) 3.23930293 4–5: 158.595°, 5–13: 128.249°, 13–4: 131.678°
4.5.14 Tetradecagonal pentagrombatoid 93.333 (93+1/3) 3.69629437 4–5: 161.322°, 5–14: 132.431°, 14–4: 135.415°
4.5.15 Pentadecagonal pentagrombatoid 120 4.26103434 4–5: 163.854°, 5–15: 136.868°, 15–4: 139.442°
4.5.16 Hexadecagonal pentagrombatoid 160 4.99618463 4–5: 166.27°, 5–16: 141.668°, 16–4: 143.852°
4.5.17 Heptadecagonal pentagrombatoid 226.667 (226+2/3) 6.0318762 4–5: 168.655°, 5–17: 147.005°, 17–4: 148.807°
4.5.18 Octadecagonal pentagrombatoid 360 7.70300825 4–5: 171.134°, 5–18: 153.216°, 18–4: 154.623°
4.5.19 Enneadecagonal pentagrombatoid 760 11.33123094 4–5: 173.983°, 5–19: 161.166°, 19–4: 162.12°
4.6.7 Heptagonal grombatoid 33.6 (33+3/5) 1.90275311 4–6: 136.05°, 6–7: 117.414°, 7–4: 129.756°
4.6.9 Enneagonal grombatoid 72 2.89261321 4–6: 152.196°, 6–9: 133.477°, 9–4: 141.065°
4.6.11 Hendecagonal grombatoid 264 5.73603815 4–6: 166.263°, 6–11: 153.945°, 11–4: 157.642°
4.7.7 Heptagonal heptagrombatoid 56 2.48443296 4–7: 142.89°, 7–7: 129.492°, 7–4: 142.89°
4.7.8 Octagonal heptagrombatoid 112 3.56438987 4–7: 154.746°, 7–8: 142.89°, 8–4: 151.854°
4.7.9 Enneagonal heptagrombatoid 504 7.67565724 4–7: 168.466°, 7–9: 161.877°, 9–4: 165.925°
5.5.6 Hexagonal cosmoid 30 1.73854608 5–5: 131.175°, 5–6: 124.248°, 6–5: 124.248°
5.5.7 Heptagonal cosmoid 46.667 (46+2/3) 2.20635222 5–5: 142.645°, 5–7: 132.431°, 7–5: 132.431°
5.5.8 Octagonal cosmoid 80 2.942284 5–5: 152.54°, 5–8: 141.668°, 8–5: 141.668°
5.5.9 Enneagonal cosmoid 180 4.49304373 5–5: 162.268°, 5–9: 153.216°, 9–5: 153.216°
5.6.7 Heptagonal hexacosmoid 210 4.69618173 5–6: 160.837°, 6–7: 156.465°, 7–5: 158.678°

Quadriverticed (21)

Vert. Conf. Name Vertices Circumradius Dihedral angles
3.3.4.4 Square tetrarectoid
Metacuboctahedron
12 1
3.3.4.5 Pentagonal tetrametarectoid 17.143 (17+1/7) 1.21514193
3.3.4.6 Hexagonal tetrametarectoid 24 1.47260268
3.3.4.7 Heptagonal tetrametarectoid 33.6 (33+3/5) 1.78710318
3.3.4.8 Octagonal tetrametarectoid 48 2.18885876
3.3.4.9 Enneagonal tetrametarectoid 72 2.74250029
3.3.4.10 Decagonal tetrametarectoid 120 3.6151889
3.3.4.11 Hendecagonal tetrametarectoid 264 5.46508259
3.4.3.5 Pentagonal tetrapararectoid 17.143 (17+1/7) 1.21514193
3.4.3.6 Hexagonal tetrapararectoid 24 1.47260268
3.4.3.7 Heptagonal tetrapararectoid 33.6 (33+3/5) 1.78710318
3.4.3.8 Octagonal tetrapararectoid 48 2.18885876
3.4.3.9 Enneagonal tetrapararectoid 72 2.74250029
3.4.3.10 Decagonal tetrapararectoid 120 3.6151889
3.4.3.11 Hendecagonal tetrapararectoid 264 5.46508259
3.3.5.5 Pentagonal pentametarectoid
Metaicosidodecahedron
30 1.61803399
3.3.5.6 Hexagonal pentametarectoid 60 2.32442133
3.3.5.7 Heptagonal pentametarectoid 210 4.42745625
3.5.3.6 Hexagonal pentapararectoid 60 2.32442133
3.5.3.7 Heptagonal pentapararectoid 210 4.42745625
3.4.4.5 Pentagonal bitetrarectoid
Metarhombicosidodecahedron
60 2.23295051