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Mathlib.RingTheory.Congruence.BigOperators

Interactions between ∑, ∏ and RingCon #

theorem RingCon.listSum {ι : Type u_1} {S : Type u_2} [AddMonoid S] [Mul S] (t : RingCon S) (l : List ι) {f : ιS} {g : ιS} (h : il, t (f i) (g i)) :
t (List.map f l).sum (List.map g l).sum

Congruence relation of a ring preserves finite sum indexed by a list.

theorem RingCon.multisetSum {ι : Type u_1} {S : Type u_2} [AddCommMonoid S] [Mul S] (t : RingCon S) (s : Multiset ι) {f : ιS} {g : ιS} (h : is, t (f i) (g i)) :
t (Multiset.map f s).sum (Multiset.map g s).sum

Congruence relation of a ring preserves finite sum indexed by a multiset.

theorem RingCon.finsetSum {ι : Type u_1} {S : Type u_2} [AddCommMonoid S] [Mul S] (t : RingCon S) (s : Finset ι) {f : ιS} {g : ιS} (h : is, t (f i) (g i)) :
t (s.sum f) (s.sum g)

Congruence relation of a ring preserves finite sum.