English
If 0 ≤ m, then m < extremalNumber(card V) H iff there exists G with H.Free G and m < |G.edgeFinset|.
Русский
Если 0 ≤ m, то \(m < \\mathrm{extremalNumber}(card V,H)\) эквивалентно существованию \(G\) с \(H.Free G\) и \(m < |G.edgeFinset|\).
LaTeX
$$\\( m \\ge 0 \\Rightarrow m < \\mathrm{extremalNumber}(\\mathrm{card} V, H) \\iff \\exists G, H.Free G \\land m < |G.edgeFinset| \\)$$
Lean4
@[inherit_doc lt_extremalNumber_iff]
theorem lt_extremalNumber_iff_of_nonneg (H : SimpleGraph W) {m : R} (h : 0 ≤ m) :
m < extremalNumber (card V) H ↔ ∃ G : SimpleGraph V, ∃ _ : DecidableRel G.Adj, H.Free G ∧ m < #G.edgeFinset :=
by
simp_rw [← Nat.floor_lt h]
exact lt_extremalNumber_iff H ⌊m⌋₊