English
The commutative semiring structure on ArithmeticFunction R satisfies the standard commutativity of multiplication with respect to addition in a defined sense.
Русский
Структура коммутативного полускольца на ArithmeticFunction R удовлетворяет стандартной коммутативности умножения относительно сложения.
LaTeX
$$proof: commutativity of multiplication in ArithmeticFunction R$$
Lean4
instance [CommRing R] : CommRing (ArithmeticFunction R) :=
{ ArithmeticFunction.instSemiring with
neg_add_cancel := neg_add_cancel
mul_comm := mul_comm
zsmul := (· • ·) }