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Nomenclature for a unital magma together with a monoid

Is there some established name/nomenclature for structures $\mathfrak{A} = (A,\, {\oplus},\, {\odot})$, where $(A,\, {\oplus})$ forms a (commutative) unital magma (in particular not associative!), $(...
blk's user avatar
  • 281
2 votes
2 answers
199 views

What is the name for a magma which is neither a quasigroup nor a semigroup yet has both an identity and inverses?

Is there a name which is more specific than `unital magma' for a magma whose only requirements are that it should have both an identity and (L/R symmetric) inverses for all elements? The following ...
KesterKester's user avatar
3 votes
0 answers
49 views

Each magma $M$ is associated with monoids $\mathcal{L}(M)$ and $\mathcal{R}(M)$. What are these called, and have they been studied?

Let $X$ denote a magma. Then $\mathrm{List}(X)$ is a monoid equipped with both a left and a right action on $X$, where the actions are defined in the obvious way. To illustrate these actions, suppose ...
goblin GONE's user avatar
  • 68.1k
5 votes
3 answers
199 views

Terminology: Semigroups, only their "binary operations" aren't closed.

Motivation: Consider $\mathcal{X}=(X, +)$, where $X=\{-1, 0, 1\}$ and $+$ is standard addition. Then $\mathcal{X}$ is associative (where defined) but not closed. NB: There is an identity element in $X$...
Shaun's user avatar
  • 45.8k
3 votes
1 answer
114 views

Name for the property of “being a Cartesian product of arbitrary sets”

Suppose I have a set $S$ of pairs (or, in general, tuples, or objects with two or more parts/attributes/projections). This set may have the property that $$(a, b) \in S \wedge (a', b') \in S \...
Kevin Reid's user avatar
2 votes
1 answer
145 views

Is there a term for this property of magmas?

There exists an element of the magma c such that for all x: $ x*x=c $ The consequence of this is that the elements on the diagonal of the Cayley table are all the same, e.a: $ * = \begin{bmatrix} 1 &...
Nathan BeDell's user avatar
7 votes
1 answer
731 views

Is there a term for an algebraic structure with two binary operators that are closed under a set?

For example, let's say we're using the operators +, and *, and the set {0,1,2} The Cayley tables look like this: ...
Nathan BeDell's user avatar
1 vote
2 answers
139 views

Is there a standard name for a set equipped only with an idempotent binary operation?

Is there a name for an idempotent magma, or do they not arise often enough to warrant a special name? (By idempotent binary operation, I mean an operation $+$ such that $x + x = x$ for any $x$.)
Roly's user avatar
  • 150
5 votes
2 answers
165 views

Is there a name for magmas with $[x+y]+[x'+y'] \equiv [x+x']+[y+y']$?

Is there a name for magmas (written additively) satsisfying the following identity? The square brackets have no particular signifance, but will hopefully promote readability in what follows. $$[x+y]+[...
goblin GONE's user avatar
  • 68.1k