
Formula for pentagonal numbers - Mathematics Stack Exchange
Jul 27, 2013 · Formula for pentagonal numbers Ask Question Asked 12 years, 4 months ago Modified 6 years, 6 months ago
How to prove Euler's pentagonal theorem? Some hints will help
Aug 5, 2011 · While there is a lot of value to the different bijective proofs known for Euler's pentagonal theorem, perhaps the proof that's easiest to see without having to draw pictures is Euler's original idea.
graph theory - polyhedron with its faces either pentagons or hexagons ...
0 A polyhedron has all its faces either pentagons or hexagons. Show that it must have at least $12$ pentagonal faces. I can show that it has exactly $12$ pentagonal faces when exactly $3$ faces meet …
Pentagonal Numbers - Mathematics Stack Exchange
Aug 26, 2015 · Pentagonal Numbers Ask Question Asked 10 years, 3 months ago Modified 10 years, 3 months ago
Is Cairo pentagonal tiling belong to pentagonal tilings type 8?
Apr 30, 2020 · I agree with you. The type 8 pentagon tiling has one degree of freedom, and although you can choose it so that clusters of four tiles form a large hexagonal shape similar to that seen in …
A New Pentagonal Tiling? Help Me Solve the Mystery
Feb 10, 2025 · Thank you for your comment! Indeed, all convex pentagonal tilings have been mapped, and the list is believed to be complete. However, for concave pentagons, there are infinitely many …
Existence of a special pentagonal tiling - Mathematics Stack Exchange
Dec 30, 2020 · Is there a pentagonal tiling composed of only one shape of pentagon so that each pentagon touches exactly 5 other pentagons? Two pentagons are in touch if they share at least one …
Three dimensional Cairo Pattern - Mathematics Stack Exchange
Jun 4, 2022 · The Cairo pentagonal tiling is an interesting tessellation of the two-dimensional plane by irregular pentagons, which is given by taking two irregular hexagonal tilings, congruent but …
Why are $10$-sided dice not bipyramids? - Mathematics Stack Exchange
Jun 12, 2019 · Commonly used $10$ -sided dice are pentagonal trapezohedrons, as opposed to pentagonal bipyramids. Given that bipyramids are a more "obvious" shape for a fair die with an even …
Euler's pentagonal number theorem, the notion of $\omega (n)$ and ...
May 3, 2023 · Then he defines the pentagonal numbers as being the number $\omega (n)$ and $\omega (-n)=\frac {3n^2+n} {2}$. I don't get what $\omega (-n)$ here represents, I need help …