inductive
definition
DBlockElement
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IndisputableMonolith.CrossDomain.TenFoldCombinations on GitHub at line 44.
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41 | l1 | l2 | l3 | l4 | l5 | s1 | s2 | s3 | s4 | s5
42 deriving DecidableEq, Repr, BEq, Fintype
43
44inductive DBlockElement where
45 | sc | ti | v | cr | mn | fe | co | ni | cu | zn -- first d-block period
46 deriving DecidableEq, Repr, BEq, Fintype
47
48theorem finger_is_10 : HasTenFold Finger := by
49 unfold HasTenFold; decide
50theorem digit_is_10 : HasTenFold DecimalDigit := by
51 unfold HasTenFold; decide
52theorem lumSac_is_10 : HasTenFold LumbarSacralVert := by
53 unfold HasTenFold; decide
54theorem dBlock_is_10 : HasTenFold DBlockElement := by
55 unfold HasTenFold; decide
56
57/-- 10 = 2 · 5 factorisation. -/
58theorem ten_eq_two_D : (10 : ℕ) = 2 * 5 := by decide
59
60/-- Two 10-folds have the same cardinality. -/
61theorem tenfold_equicardinal
62 {A B : Type} [Fintype A] [Fintype B]
63 (hA : HasTenFold A) (hB : HasTenFold B) :
64 Fintype.card A = Fintype.card B := by
65 rw [hA, hB]
66
67/-- 10 × 10 = 100. -/
68theorem tenfold_squared
69 {A B : Type} [Fintype A] [Fintype B]
70 (hA : HasTenFold A) (hB : HasTenFold B) :
71 Fintype.card (A × B) = 100 := by
72 unfold HasTenFold at hA hB
73 simp [Fintype.card_prod, hA, hB]
74