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Every surface can be triangulated in such a way that at most 7 trianlges meet at one vertex. Every surface can be decomposed in squares such that at every vertex at most 5 suqares meet. For surfaces of genus more than 1 this is the low bound.

What happen in higher dimensions, for example for 3 and 4-manifolds, ect...? What is the minimal number of simplexes of cubes that we It should alow be easy to meet show that for every dimension $n$ there are numbers $S(n)$ and and $C(n)$ such that every manifold $M^n$ admits a simplicial decomposition with at one most $S(n)$ simplexes at every vertex ? It is reasonable to guess that the number of cubes should be and a cubical decomposition with at least most $2^n$, where n is the dimensionC(n)$ cubes at every vertex. But is The refference of Gil below confirms this known for $n>2$? n=3$.

Here are three questions (Notice I suspect they are hard).

1) Can it be proven that only faces of the same dimension should $C(n)>2^n$?

2) Can it be glued, i.e., we can not glue a vertex to an interior point proven that $S(n)>\frac{Vol(S^n)}{Vol(\Delta^n)}$, where $\Delta^n$ is the spherical tetrahedron with edge of an edge).length $\frac{\pi}{3}$ in the unit sphere $S^n$.

3) Is there any reasonable estimation for $C(n)$ and $S(n)$ from above?

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Simplicial and cubical decompositions of low valence

Every surface can be triangulated in such a way that at most 7 trianlges meet at one vertex. Every surface can be decomposed in squares such that at every vertex at most 5 suqares meet. For surfaces of genus more than 1 this is the low bound.

What happen in higher dimensions, for example for 3 and 4-manifolds, ect...? What is the minimal number of simplexes of cubes that we should alow to meet at one vertex? It is reasonable to guess that the number of cubes should be at least $2^n$, where n is the dimension. But is this known for $n>2$?

(Notice that only faces of the same dimension should be glued, i.e., we can not glue a vertex to an interior point of an edge).