#20144 ⟨a, b | aab=b, bbaa=aaa⟩
Contents
- Properties
- Finite structure
- Cayley table
- Right Cayley graph
- Left Cayley graph
- Rewriting system
- Same cardinality
- Sum of relation sides is 11
- Finite non-commutative monoid with 15 elements
- Not cancellative, because multiplication by b is not injective:
-
b ⋅ b4 = b and b ⋅ 1 = b, however b4 ≠ 1
Elements in the center commute with all other elements.
An idempotent element x satisfies x2 = x.
The index and period of x is the least m (index) and n (period) such that x(m+n) = xm.
- 1 element center:
- 3 non-trivial idempotents:
- Order of generators:
- a: index 3, period 2
- b: index 1, period 4
- Histogram:
| index 1, period 1 | 3 elements | b2a, b4, b4a2 |
| index 1, period 2 | 3 elements | b2, b2a2, b4a |
| index 1, period 4 | 6 elements | b, ba, ba2, b3, b3a, ... |
| index 2, period 1 | 1 element | a2 |
| index 3, period 2 | 1 element | a |
Idempotents are shown in bold.
|
1 | a | b | a2 | ba | b2 | ba2 | b2a | b3 | b2a2 | b3a | b4 | b3a2 | b4a | b4a2 |
| 1 | 1 | a | b | a2 | ba | b2 | ba2 | b2a | b3 | b2a2 | b3a | b4 | b3a2 | b4a | b4a2 |
| a | a | a2 | b3 | b2a2 | b3a | b4 | b3a2 | b4a | b | b4a2 | ba | b2 | ba2 | b2a | b2a2 |
| b | b | ba | b2 | ba2 | b2a | b3 | b2a2 | b3a | b4 | b3a2 | b4a | b | b4a2 | ba | ba2 |
| a2 | a2 | b2a2 | b | b4a2 | ba | b2 | ba2 | b2a | b3 | b2a2 | b3a | b4 | b3a2 | b4a | b4a2 |
| ba | ba | ba2 | b4 | b3a2 | b4a | b | b4a2 | ba | b2 | ba2 | b2a | b3 | b2a2 | b3a | b3a2 |
| b2 | b2 | b2a | b3 | b2a2 | b3a | b4 | b3a2 | b4a | b | b4a2 | ba | b2 | ba2 | b2a | b2a2 |
| ba2 | ba2 | b3a2 | b2 | ba2 | b2a | b3 | b2a2 | b3a | b4 | b3a2 | b4a | b | b4a2 | ba | ba2 |
| b2a | b2a | b2a2 | b | b4a2 | ba | b2 | ba2 | b2a | b3 | b2a2 | b3a | b4 | b3a2 | b4a | b4a2 |
| b3 | b3 | b3a | b4 | b3a2 | b4a | b | b4a2 | ba | b2 | ba2 | b2a | b3 | b2a2 | b3a | b3a2 |
| b2a2 | b2a2 | b4a2 | b3 | b2a2 | b3a | b4 | b3a2 | b4a | b | b4a2 | ba | b2 | ba2 | b2a | b2a2 |
| b3a | b3a | b3a2 | b2 | ba2 | b2a | b3 | b2a2 | b3a | b4 | b3a2 | b4a | b | b4a2 | ba | ba2 |
| b4 | b4 | b4a | b | b4a2 | ba | b2 | ba2 | b2a | b3 | b2a2 | b3a | b4 | b3a2 | b4a | b4a2 |
| b3a2 | b3a2 | ba2 | b4 | b3a2 | b4a | b | b4a2 | ba | b2 | ba2 | b2a | b3 | b2a2 | b3a | b3a2 |
| b4a | b4a | b4a2 | b3 | b2a2 | b3a | b4 | b3a2 | b4a | b | b4a2 | ba | b2 | ba2 | b2a | b2a2 |
| b4a2 | b4a2 | b2a2 | b | b4a2 | ba | b2 | ba2 | b2a | b3 | b2a2 | b3a | b4 | b3a2 | b4a | b4a2 |
Idempotents are shown in bold.
Idempotents are shown in bold.
- Reduction order:
- Left-to-right recursive path with deg(b) = 0; deg(a) = 1
- Certificate: derivations of all rewriting rules from the defining relations.
# ab:aab=b,bbaa=aaa b/a - -
bbbbb=b
ab=bbb
aaa=bbaa
22 unique, 190 total
| Σ | # | Presentation | Properties | Description | φ |
| 9 | 1602 | ⟨a, b | aaa=bb, aba=a⟩ | Noc 15 | | 2 |
| 9 | 1603 | ⟨a, b | aaa=bb, aba=b⟩ | Noc 15 | | 1 |
| 9 | 1751 | ⟨a, b | aaab=1, bbbbb=1⟩ | Grp Com 15 | ℤ15 | 138 |
| 9 | 1993 | ⟨a, b | aaa=a, abbb=b⟩ | Noc 15 | | 4 |
| 10 | 5342 | ⟨a, b | aaa=bb, aba=aa⟩ | Noc 15 | | 1 |
| 10 | 5344 | ⟨a, b | aaa=bb, aba=bb⟩ | Noc 15 | | 2 |
| 10 | 6276 | ⟨a, b | aaa=a, bbbbb=a⟩ | Noc Com 15 | ℕ(15 = 5) | |
| 10 | 6316 | ⟨a, b | aaa=b, bbbbb=a⟩ | Noc Com 15 | ℕ(15 = 1) | |
| 10 | 6317 | ⟨a, b | aaa=b, bbbbb=b⟩ | Noc Com 15 | ℕ(15 = 3) | |
| 11 | 12981 | ⟨a, b | abb=aaa, baaa=b⟩ | Noc 15 | | 3 |
| 11 | 12985 | ⟨a, b | abb=aaa, baba=b⟩ | Noc 15 | | 7 |
| 11 | 13123 | ⟨a, b | aab=aaa, aba=bb⟩ | Noc 15 | | |
| 11 | 13191 | ⟨a, b | abb=aaa, bbb=ab⟩ | Noc 15 | | 1 |
| 11 | 13192 | ⟨a, b | abb=aaa, bbb=ba⟩ | Noc 15 | | |
| 11 | 15439 | ⟨a, b | aaa=aa, bbbbb=a⟩ | Noc Com 15 | ℕ(15 = 10) | |
| 11 | 15503 | ⟨a, b | aaa=ab, bbbbb=a⟩ | Noc Com 15 | ℕ(15 = 6) | 1 |
| 11 | 15543 | ⟨a, b | aaa=bb, bbbbb=a⟩ | Noc Com 15 | ℕ(15 = 2) | 1 |
| 11 | 16041 | ⟨a, b | aaa=ab, bbbb=aa⟩ | Noc 15 | | |
| 11 | 16142 | ⟨a, b | aab=aa, bbbb=ab⟩ | Noc 15 | | |
| 11 | 19374 | ⟨a, b | aaa=b, bbbbb=ab⟩ | Noc Com 15 | ℕ(15 = 4) | |
| 11 | 19502 | ⟨a, b | aab=a, bbbbb=ba⟩ | Noc 15 | | 1 |
| 11 | 20819 | ⟨a, b | ab=aa, bbaaa=bb⟩ | Noc 15 | | 6 |