Lax Lean Archive

Proof of `Homomorphism counts from a disjoint union`

groundedproofs/Lax871432Proofs/Results.lean · lax-871432

What this proof establishes

no assumptions

lem✓Lax871432.CoproductCounts

Assuming the claims on the left, the claim on the right holds — checked by the archive's pipeline. Proof code is not displayed here.

Read the Lean proof on GitHub

In the paper

  • page 3 of this submission's paper

Description

eq:coproducteq:coproduct. Restricting a homomorphism out of F1⊕gF2F₁ ⊕g F₂ to the two parts is a bijection onto pairs of homomorphisms out of F1F₁ and out of F2F₂, since there are no edges between the parts.