The Groups p3, p31m, p3m1,
p6, and p6m
These five groups are intimately related, so we handle them all in a single
table.
| | |
| Generators: |
| p3 | = | {t1, R3} |
| p31m | = | {t1, R3, Mx} |
| p3m1 | = | {t1, R3, My} |
| p6 | = | {t1, R6} |
| p6m | = | {t1, R6, Mx} |
|
|
| Relations: |
t2 = R3 t1
R3-1,
R33 = e,
R3-1 t1
R3 = t1-1
t2-1
R62 = R3,
R6 Mx = My
| |
|
| Cell diagram: | |
|
The possibilities for homomorphisms from these groups is smaller than one
might guess from the list of generators, because t1 and
R3 can never be negating isometries of any pattern. To
see this note that R cannot go to -1
because its order is odd, and that t1 cannot go to -1, because then t2 and the product
t2 t1 would also be taken to
-1, which would give a contradiction.
We group all the homomorphisms in one table.
Table:
Eleven homomorphisms from groups related to p3
| type |
P(k) = -1 |
wallpaper type of kernel group, with remarks |
p3
![[Image]](../../../buttons/image.gif) |
none |
E = G = p3 |
p31m
![[Image]](../../../buttons/image.gif) |
none |
E = G = p31m |
p31m'
![[Image]](../../../buttons/image.gif) |
Mx |
E = p31m,
G = p3 = {t1, R3} |
p3m1
![[Image]](../../../buttons/image.gif) |
none |
E = G = p3m1 |
p3m'
![[Image]](../../../buttons/image.gif) |
My |
E = p3m1, G = p3 |
p6
![[Image]](../../../buttons/image.gif) |
none |
E = G = p6 |
p6'
![[Image]](../../../buttons/image.gif) |
R6 |
E = p6,
G = p3 = {t1, R62} |
p6m
![[Image]](../../../buttons/image.gif) |
none |
E = G = p6m |
p6m'm'
![[Image]](../../../buttons/image.gif) |
Mx |
E = p6m, G = p6 |
p6'm'm
![[Image]](../../../buttons/image.gif) |
R6 |
E = p6m,
G = p31m =
{t1, R62, Mx};
My negative |
p6'mm'
![[Image]](../../../buttons/image.gif) |
R6 and Mx |
E = p6m,
G = p3m1 =
{t1, R62,
R6 Mx};
My positive |
Communications in Visual Mathematics, vol 1, no 1, August 1998.
Copyright © 1998,
The Mathematical Association of America.
All rights reserved.
Created: 08 Jul 1998 ---
Last modified: 18 Aug 1998 23:59:59
Comments to: CVM@maa.org