# tetrahedron

## Primary tabs

Defines:
regular tetrahedron
Keywords:
Polyhedron
Type of Math Object:
Definition
Major Section:
Reference
Groups audience:

## Mathematics Subject Classification

### n-agons and polyhedrons

The definition of n-agons and polyhedrons can be exposed in only one entry. I don't see the utility to display so many entries for definitions that are analogous and, beside the point, trivial.

### Re: n-agons and polyhedrons

the proper way, of course
is to mention this on the "polyhedron" entry
nd then addind "tetrahedron" to the "also defines" field on the edit entry dialog
f
G -----> H G
p \ /_ ----- ~ f(G)
\ / f ker f
G/ker f

### not necessarily

As you can see, there are a lot of things which can be said about tetrahedra which are not special cases of general facts. Therefore, it is good for the tertrahedra to have their own special place.

I just read your article and it was totally great, it contains a lot of useful ideas, it is also written in organize manner,thanks for sharing this kind of article.

### I like it

I think I have a greater understanding of a tetrahedron now, your explanation was simple enough. I was thinking of studying mathematics at university, but instead opted to go into computing, repair diagnostics, sys backup & recovery etc... which has turned out to be most helpful for me, at least.

### pseudoprimes in k(i) (contd)- a small by-product

A small by-product of research in area of pseudoprimes in k(i): Take a product of two numbers each with shape 4m+3. Let x be this composite number. x is pseudo to base (x-1).Examples 21, 33, 57 etc. (20^20-1)/21 yields a rational integer.

### Fermat's theorem in terms of matrices.

Let X be a square matrix in which each element is an odd prime. Then (a^(X-I)-I)/X yields a square matrix in which the elements belong to Z. Here a is co-prime with each element of X. Also I is the identity matrix.

### A request to Dr. Puzio

I use pari software and sometimes I would like to display the calculations/programs on the space for messages; however, I am unable to paste them. Would be glad if this and adding files are enabled.

### A puzzle

Fermat’s theorem works in terms of square matrices; however Euler’s generalisation of Fermat’s theorem in terms of matrices does not seem to be true.