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Mathlib.Algebra.BigOperators.Multiset.Lemmas

Lemmas about Multiset.sum and Multiset.prod requiring extra algebra imports #

theorem Multiset.dvd_prod {α : Type u_1} [CommMonoid α] {s : Multiset α} {a : α} :
a ∈ s → a ∣ s.prod
@[simp]
theorem Multiset.prod_map_neg {α : Type u_1} [CommMonoid α] [HasDistribNeg α] (s : Multiset α) :
(Multiset.map Neg.neg s).prod = (-1) ^ Multiset.card s * s.prod
theorem Multiset.prod_eq_zero {α : Type u_1} [CommMonoidWithZero α] {s : Multiset α} (h : 0 ∈ s) :
s.prod = 0
@[simp]
theorem Multiset.prod_eq_zero_iff {α : Type u_1} [CommMonoidWithZero α] [NoZeroDivisors α] [Nontrivial α] {s : Multiset α} :
s.prod = 0 ↔ 0 ∈ s
theorem Multiset.prod_ne_zero {α : Type u_1} [CommMonoidWithZero α] [NoZeroDivisors α] [Nontrivial α] {s : Multiset α} (h : 0 ∉ s) :
s.prod ≠ 0
theorem Multiset.dvd_sum {α : Type u_1} [NonUnitalSemiring α] {s : Multiset α} {a : α} :
(∀ x ∈ s, a ∣ x) → a ∣ s.sum
theorem Commute.multiset_sum_right {α : Type u_1} [NonUnitalNonAssocSemiring α] (s : Multiset α) (a : α) (h : ∀ b ∈ s, Commute a b) :
Commute a s.sum
theorem Commute.multiset_sum_left {α : Type u_1} [NonUnitalNonAssocSemiring α] (s : Multiset α) (b : α) (h : ∀ a ∈ s, Commute a b) :
Commute s.sum b