Theorems · Theorem · group theory

Finset.sum_pi_single

∀ {ι : Type u_1} {M : ι → Type u_6} [inst : DecidableEq ι] [inst_1 : (a : ι) → AddCommMonoid (M a)] (a : ι)
  (f : (a : ι) → M a) (s : Finset ι), ∑ a' ∈ s, Pi.single a' (f a') a = if a ∈ s then f a else 0

Defined in

Mathlib.Algebra.BigOperators.Group.Finset.Piecewise

Cited by

8 results in Mathlib

Foundations

Depth 71 from the axioms · uses propext, Classical.choice, Quot.sound

Assumes

DecidableEqAddCommMonoid