English
The structure MonoidAlgebra R M forms a nonassociative ring when M is a MulOneClass monoid; associativity is not assumed or required for the multiplication.
Русский
Структура MonoidAlgebra R M образует неассоциативное кольцо, если M — моноид MulOneClass; ассоциативность умножения не требуется.
LaTeX
$$$\\mathrm{NonAssocRing}(\\mathrm{MonoidAlgebra}(R,M)).$$$
Lean4
@[to_additive (dont_translate := R)]
instance nonAssocRing [MulOneClass M] : NonAssocRing (MonoidAlgebra R M)
where
intCast z := single 1 z
intCast_ofNat n := by simp [natCast_def]
intCast_negSucc n := by simp [natCast_def, one_def]