∀ {μ : YoungDiagram} (entry : ℕ → ℕ → ℕ) (row_weak' : ∀ {i j1 j2 : ℕ}, j1 < j2 → (i, j2) ∈ μ → entry i j1 ≤ entry i j2)
  (col_strict' : ∀ {i1 i2 j : ℕ}, i1 < i2 → (i2, j) ∈ μ → entry i1 j < entry i2 j)
  (zeros' : ∀ {i j : ℕ}, (i, j) ∉ μ → entry i j = 0),
  sizeOf { entry := entry, row_weak' := row_weak', col_strict' := col_strict', zeros' := zeros' } = 1