Dr David McGrath
Spine Physician
MB BS (Hons) FAFOM, RACP, FAFMMMaster of Pain Medicine
The vertex semigroup structure is a 4semigroup (one of 126 possibilities)
LR Ideals |
1=xyx L |
2=xyz L |
3=zyx L |
4=zyz L |
1=xyx R | 1 | 2 | 1 | 2 |
2=xyz R | 1 | 2 | 1 | 2 |
3=zyx R | 3 | 4 | 3 | 4 |
4=zyz R | 3 | 4 | 3 | 4 |
1.Idempotent aa=a
2.Associative (ab)c=a(bc)
3.Rectangular abc=ac. aba=a (aa =a) (point1)
1 | 2 | 3 | 4 | |
L | 1133 | 2244 | 1133 | 2244 |
R | 1212 | 1212 | 3434 | 3434 |
J |
xxxx |
yyyy |
yyyy |
xxxx |
L,R Classes L={ (13), (24) } and R={ (12), (34) }
(1L3, 2L4) and (1R2, 3R4)
J Classes J={ (14) , (23) }
SaS=SbS
H Classes
aLb=aRb eg 1L2=1R2 ie not possible no H class, except trivial aLa=aRa
D Class D={ (14), (23) }
(1R2,2L4) and/or (4R3 ,3L1) implies (1,4) belong same D class.
(3R4,4L2) and/or (2R1,1L3) implies (2,3) belong same D class.
R Classes | 11 | 22 | |
33 |
L Class (f) 1133 ff=f(2) |
D Class (g) 2233 ff=f(2) |
(a) Z2 1233* ff=f (1) (2133) fff=f (3) |
44 |
D Class (h) 1144 ff=f(2)
|
L Class (e) 2244 ff=f (2) |
(b) Z2 1244* ff=f (1) (2144) fff=f(3) |
(c) Z2 1134* ff=f(1) (1143) fff=f(3) |
(d) Z2 2234* ff=f(1) (2243)fff=f(3) |
(i) Klein 4-Group (2134) fff=f(2) (2143) fff=f(4) 1234* ff=f(0) (1243) fff=f(2) |
(brackets)=number of category changes and generative set. ff..=cycle length
Set fff=f | 2134 | 2143 | 1243 | 1143 | 2243 | 2133 | 2144 |
Inverses | 2134 | 2143 | 1243 | - | - | - | - |
Single Permutation Set ff=f | 1234 | 1134 | 2234 | 1244 | 1233 |
A generative set can be identified. Each Z2 group has one generative permutation (1143,2243,2133,2144).
The K4 group has 3 (2134,2143,1243) (all produce the identity). All others can be derived. The generative set are all 3power idempotent.
bd | 1244 | (2144) | 2234 | (2243) | |
1244 | 1244 |
(2144) | 2244 | 2233 | |
(2144) | (2144) | 1244 | 2244 | 2233 | |
2234 | 2244 | 1144 | 2234 | (2243) | |
(2243) | 2444 | 1144 | (2243) | 2234 |
Non Closed structure with 2 -Z2 subgroups (1244,2144) (2234, 2243)
bc | 1244 | (2144) | 1134 | (1143) | |
1244 | 1244 | (2144) | 1144 | 1133 | |
(2144) | (2144) | 1244 | 1144 | 1133 | |
1134 | 1144 | 2244 | 1134 | (1143) | |
(1143) | 1144 | 2244 | (1143) | 1134 |
Klein 4-Group (i=1234,aa=i,ab=ba)
4-Group Z2xZ2 Klein 4-Group with three subgroups (#1234,#2143) (1234,1243) (1234,2134)
ib | 1234 | (2143) | (1243) | (2134) | 1244 | (2144) | |
L | L | ||||||
1234 | 1234 | 2143 | 1243 | 2134 | 1244 | (2144) | |
2143 | 2143 | 1234 | 2134 | 1243 | (2144) | 1244 | |
1243 | 1243 | 2134 | 1234 | 2143 | 1244 | (2144) | |
2134 | 2134 | 1243 | 2143 | 1243 | (2144) | 1244 | |
1244 | R | 1244 | (2133) | 1233 | (2144) | 1244 | (2144) |
(2144) | R | (2144) | 1233 | (2133) | 1244 | (2144) | 1244 |
ie | 1234 |
(2143) | (1243) | (2134) | 2244 | |
L | ||||||
1234 | 1234 | 2143 | 1243 | 2134 | 2244 | |
(2143) | 2143 | 1234 | 2134 | 1243 | 2244 | |
(1243) | 1243 | 2134 | 1234 | 2143 | 2244 | |
(2134) | 2134 | 1243 | 2143 | 1243 | 2244 | |
2244 | R | 2244 | 1133 | 2233 | 1144 | 2244 |
(e,f,g,h) Idempotent 4-Semigroup and (b) Z2 group
Idempotent 4-Semigroup with (2) 2-subsemigroups (1133,2244) and (1144,2233)
(c,d) 4-Semigroup
4-Semigroup with 2 Z2 groups (1134,1143) and (2234,2243)
Closed under Binary Function composition. (fg) belongs set of 16 functions.
Transformation Semigroup is a pair (N,S) N=(1,3,2,4) and S=(16 functions, closed under composition)
Not the full transformation semigroup, S4xS4=256 functions (n^n)
Only (0,1) functions supported by B2(Y). ie (1234), (1134), (1233),(2234),(1244).
©Copyright 2007 Dr David McGrath. All rights reserved