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Erdős problem 426

We say HH is a unique subgraph of GG if there is exactly one way to find HH as a subgraph (not necessarily induced) of GG. Is there a graph on nn vertices with ≫2(n2)n!\gg \frac{2^{\binom{n}{2}}}{n!} many distinct unique subgraphs?

Sources

The source's own material, retained exactly.

2 retained statements36c6d0fef71a

Open selected source

FormalConjectures/ErdosProblems/

426.lean

Retained formal statement2 of 2

Sanity check: the empty graph ⊥ is a unique subgraph of itself. Its only subgraph is ⊥ (everything ≤ ⊥ equals ⊥), which is isomorphic to ⊥ via the identity.

FormalConjectures/ErdosProblems/426.leanErdos426.isUniqueSubgraph_bot_bot1 lineExact file
∀ {V : Type u_1}, ⊥.IsUniqueSubgraph ⊥
TestStatement only, no proof