#18750 ⟨
a
,
b
|
aaa
=
a
,
babbab
=
a
⟩
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Monoid enumeration
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#18749
⟨
a
,
b
|
aaa
=
a
,
bababb
=
b
⟩
Next:
#18751
⟨
a
,
b
|
aaa
=
a
,
babbab
=
b
⟩
Contents
Properties
Commutative structure
Staircase diagram
Rewriting system
Properties
Sum of relation sides is 11
Infinite non-cancellative commutative monoid
Element
b
has infinite order
Not cancellative, because multiplication by
a
is not injective:
a
⋅
a
2
=
a
and
a
⋅ 1 =
a
, however
a
2
≠ 1
Commutative structure
Gröbner basis: ⟨
a
,
b
|
a
3
=
a
,
a
b
4
=
a
2
⟩
Cancellative quotient is isomorphic to ℤ
8
Enveloping group is isomorphic to ℤ
8
Group of units is isomorphic to ℤ
1
3 Archimedian components:
1,
a
,
b
Staircase diagram
Rewriting system
Format:
Pretty
Plain
Word:
Enter a word above to compute its normal form. Tips:
Lowercase letters stand for generators.
Spaces are ignored.
Numbers repeat the previous letter, e.g.
b90
.
Strategy:
Leftmost
Rightmost
Result:
1
1
Reduction order:
Left-to-right shortlex with
a
<
b
Certificate
: derivations of all rewriting rules from the defining relations.
#
Rule
Proof
1.
ba
⇒
ab
[5]
2.
a
3
⇒
a
[1]
3.
a
b
4
⇒
a
2
[7]
# ab:aaa=a,babbab=a ab - - ba=ab aaa=a abbbb=aa
