Rearrange the digits in ⟨1263045⟩ to meet the rules below.
⟨6th 5th 4th 3rd 2nd 1st 0th⟩
✅Match
⟨⋯ 2 ⋯ 3 ⋯⟩
⟦4,6⟧ ∋ 2,5
2nd → a, 0th → b, a+b=11
Jump(0,6) = 3
⟨⋯ 3 ⋯ 1 ⋯⟩
#125034_v2.7
┌───┬───┬───┬───┬───┬───┬───┐
│6th│5th│4th│3rd│2nd│1st│0th│▒
╞═══╪═══╪═══╪═══╪═══╪═══╪═══╡▒
Step 1 │ │ │ │ │ 5 │ │ │▒
├───┼───┼───┼───┼───┼───┼───┤▒
Step 2 │ │ │ │ │ 5 │ │ 6 │▒
├───┼───┼───┼───┼───┼───┼───┤▒
Step 3 │ │ │ 0 │ │ 5 │ │ 6 │▒
├───┼───┼───┼───┼───┼───┼───┤▒
Step 4 │ │ 2 │ 0 │ │ 5 │ │ 6 │▒
├───┼───┼───┼───┼───┼───┼───┤▒
Step 5 │ │ 2 │ 0 │ 3 │ 5 │ │ 6 │▒
├───┼───┼───┼───┼───┼───┼───┤▒
Step 6 │ │ 2 │ 0 │ 3 │ 5 │ 1 │ 6 │▒
├───┼───┼───┼───┼───┼───┼───┤▒
Step 7 │ 4 │ 2 │ 0 │ 3 │ 5 │ 1 │ 6 │▒
└───┴───┴───┴───┴───┴───┴───┘▒
▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒
Proof of 2024-10-15 Q1(m=6)
═══════════════════════════
Notation: if nth -> a, then we write [nth] = a.
By ✅「2nd → a, 0th → b, a+b=11」, we have
(1) { [2nd], [0th] } = {5,6}.
By ✅「⟦4,6⟧ ∋ 2,5」, the right corner (0th) cannot be 5. Therefore, we get
┌───┬───┬───┬───┬───┬───┬───┐
│6th│5th│4th│3rd│ 2■│1st│ 0■│▒
╞═══╪═══╪═══╪═══╪═══╪═══╪═══╡▒
Step 1 │ │ │ │ │ 5 │ │ │▒
├───┼───┼───┼───┼───┼───┼───┤▒
Step 2 │ │ │ │ │ 5 │ │ 6 │▒
└───┴───┴───┴───┴───┴───┴───┘▒
▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒
--- Idle ---
┌───┬───┬───┬───┬───┬───┬───┐
│ 1 │ 2 │ │ 3 │ 0 │ 4 │ │
└───┴───┴───┴───┴───┴───┴───┘
Then, it follows from ✅「Jump(0,6) = 3」 that [4th] = 0:
┌───┬───┬───┬───┬───┬───┬───┐
│6th│5th│ 4■│3rd│2nd│1st│0th│▒
╞═══╪═══╪═══╪═══╪═══╪═══╪═══╡▒
│ │ │ │ │ 5 │ │ 6 │▒
├───┼───┼───┼───┼───┼───┼───┤▒
Step 3 │ │ │ 0 │ │ 5 │ │ 6 │▒
└───┴───┴───┴───┴───┴───┴───┘▒
▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒
--- Idle ---
┌───┬───┬───┬───┬───┬───┬───┐
│ 1 │ 2 │ │ 3 │ │ 4 │ │
└───┴───┴───┴───┴───┴───┴───┘
Next, we consider how to place 2. Combining ✅「⟨⋯ 2 ⋯ 3 ⋯⟩」 with ✅「⟨⋯ 3 ⋯ 1 ⋯⟩」, we have the following required pattern:
(2) ⟨⋯ 2 ⋯ 3 ⋯ 1 ⋯⟩.
In particular, we need to reserve two empty boxes at the right of 2 for placing 3,1. Noting that ✅「⟦4,6⟧ ∋ 2,5」 implies 2 is not at the left corner, we finish by
┌───┬───┬───┬───┬───┬───┬───┐
│ 6■│ 5■│4th│ 3■│2nd│ 1■│0th│▒
╞═══╪═══╪═══╪═══╪═══╪═══╪═══╡▒
│ │ │ 0 │ │ 5 │ │ 6 │▒
├───┼───┼───┼───┼───┼───┼───┤▒
Step 4 │ │ 2 │ 0 │ │ 5 │ │ 6 │▒
├───┼───┼───┼───┼───┼───┼───┤▒
Step 5 │ │ 2 │ 0 │ 3 │ 5 │ │ 6 │▒
├───┼───┼───┼───┼───┼───┼───┤▒
Step 6 │ │ 2 │ 0 │ 3 │ 5 │ 1 │ 6 │▒
├───┼───┼───┼───┼───┼───┼───┤▒
Step 7 │ 4 │ 2 │ 0 │ 3 │ 5 │ 1 │ 6 │▒
└───┴───┴───┴───┴───┴───┴───┘▒
▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒
--- Idle ---
┌───┬───┬───┬───┬───┬───┬───┐
│ │ │ │ │ │ │ │
└───┴───┴───┴───┴───┴───┴───┘
Q.E.D.
#125034_v2.7