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lemma

triangular_0

proved
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module
IndisputableMonolith.Gap45.PhysicalMotivation
domain
Gap45
line
87 · github
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IndisputableMonolith.Gap45.PhysicalMotivation on GitHub at line 87.

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formal source

  84theorem triangular_rec_at_8 : triangular 9 = triangular 8 + 9 := by rfl
  85
  86/-- T(0) = 0. -/
  87@[simp] lemma triangular_0 : triangular 0 = 0 := rfl
  88
  89/-- T(1) = 1. -/
  90@[simp] lemma triangular_1 : triangular 1 = 1 := rfl
  91
  92/-- T(2) = 3. -/
  93@[simp] lemma triangular_2 : triangular 2 = 3 := rfl
  94
  95/-- T(3) = 6. -/
  96@[simp] lemma triangular_3 : triangular 3 = 6 := rfl
  97
  98/-- T(4) = 10. -/
  99@[simp] lemma triangular_4 : triangular 4 = 10 := rfl
 100
 101/-- T(5) = 15. -/
 102@[simp] lemma triangular_5 : triangular 5 = 15 := rfl
 103
 104/-- T(8) = 36. -/
 105@[simp] lemma triangular_8 : triangular 8 = 36 := rfl
 106
 107/-- **KEY RESULT**: T(9) = 45. -/
 108@[simp] theorem triangular_9_is_45 : triangular 9 = 45 := rfl
 109
 110/-! ## The Closure Principle -/
 111
 112/-- The 8-tick period (from ledger coverage of 2^D with D=3). -/
 113def eight_tick : ℕ := 8
 114
 115/-- The closure number: to close an 8-tick cycle, you need 8+1 = 9 steps.
 116    This is the "fence-post" principle: 8 sections need 9 posts. -/
 117def closure_number : ℕ := eight_tick + 1