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Theorems · Theorem · combinatorics

Fintype.eq_of_subsingleton_of_sum_eq

∀ {M : Type u_4} [inst : AddCommMonoid M] {ι : Type u_5} [Subsingleton ι] {s : Finset ι} {f : ι → M} {b : M},
  ∑ i ∈ s, f i = b → ∀ i ∈ s, f i = b

If a sum of a Finset of a subsingleton type has a given value, so do the terms in that sum.

Defined in
Mathlib.Data.Fintype.BigOperators
Cited by
1 results in Mathlib
Foundations
Depth 68 from the axioms · uses propext, Classical.choice, Quot.sound
Assumes
AddCommMonoidSubsingleton

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