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2026-01-20 WR

Rearrange the digits in ⟨125034⟩ to meet the rules below.

⟨ ⁵ᵗʰ▨ ⁴ᵗʰ▨ ³ʳᵈ▨ ²ⁿᵈ▨ ¹ˢᵗ▨ ⁰ᵗʰ▨ ⟩

✅Match
⟨⋯ Perm(0,1,5) ⋯⟩
min ⊢4⊣ ≤ 2

⛔Avoid
Jump(0,2) ≤ 2
⟦0,3⟧ ∋ 1,5
⟨⋯ 0 ⋯ a ⋯⟩, a = 3|4|5

#125034_v2.11


       ┌───┬───┬───┬───┬───┬───┐
       │5th│4th│3rd│2nd│1st│0th│▒
       ╞═══╪═══╪═══╪═══╪═══╪═══╡▒
Step 1 │   │   │   │   │ 0 │   │▒
       ├───┼───┼───┼───┼───┼───┤▒
Step 2 │ 2 │   │   │   │ 0 │   │▒
       ├───┼───┼───┼───┼───┼───┤▒
Step 3 │ 2 │   │   │   │ 0 │ 1 │▒
       ├───┼───┼───┼───┼───┼───┤▒
Step 4 │ 2 │   │   │ 5 │ 0 │ 1 │▒
       ├───┼───┼───┼───┼───┼───┤▒
Step 5 │ 2 │ 4 │   │ 5 │ 0 │ 1 │▒
       ├───┼───┼───┼───┼───┼───┤▒
Step 6 │ 2 │ 4 │ 3 │ 5 │ 0 │ 1 │▒
       └───┴───┴───┴───┴───┴───┘▒
        ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒

Proof of 2026-01-20 WR
══════════════════════

Notation: if nth -> a, then we write [nth] = a.

We consider where to place 0. To avoid ⛔「⟨⋯ 0 ⋯ a ⋯⟩, a = 3|4|5」, we need

(1) 3,4,5 are to the left of 0.

It implies

(2) 0 = [2nd] | [1st] | [0th].

(3) We show that 0 = [1st] actually.

------------------------------

(3.1) If 0 = [2nd], then by (1), we have

┌───┬───┬───┬───┬───┬───┐
│5th│4th│3rd│2nd│1st│0th│
╞═══╪═══╪═══╪═══╪═══╪═══╡
│345│345│345│ 0 │1 2│1 2│
└───┴───┴───┴───┴───┴───┘

and we will match ⛔「Jump(0,2) ≤ 2」, which is not allowed.

(3.2) Else if 0 = [0th], then to match ✅「⟨⋯ Perm(0,1,5) ⋯⟩」, we need

┌───┬───┬───┬───┬───┬───┐
│5th│4th│3rd│2nd│1st│0th│
╞═══╪═══╪═══╪═══╪═══╪═══╡
│   │   │   │1 5│1 5│ 0 │
└───┴───┴───┴───┴───┴───┘

and we will match ⛔「⟦0,3⟧ ∋ 1,5」, which is also not allowed.

------------------------------

We have verified (3) and get

       ┌───┬───┬───┬───┬───┬───┐
       │5th│4th│3rd│2nd│ 1■│0th│▒
       ╞═══╪═══╪═══╪═══╪═══╪═══╡▒
Step 1 │   │   │   │   │ 0 │   │▒
       └───┴───┴───┴───┴───┴───┘▒
        ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒

--- Idle ---
┌───┬───┬───┬───┬───┬───┐
│ 1 │ 2 │ 5 │   │ 3 │ 4 │
└───┴───┴───┴───┴───┴───┘

Then, in view of ⛔「Jump(0,2) ≤ 2」, we have

       ┌───┬───┬───┬───┬───┬───┐
       │ 5■│4th│3rd│2nd│1st│0th│▒
       ╞═══╪═══╪═══╪═══╪═══╪═══╡▒
       │   │   │   │   │ 0 │   │▒
       ├───┼───┼───┼───┼───┼───┤▒
Step 2 │ 2 │   │   │   │ 0 │   │▒
       └───┴───┴───┴───┴───┴───┘▒
        ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒

--- Idle ---
┌───┬───┬───┬───┬───┬───┐
│ 1 │   │ 5 │   │ 3 │ 4 │
└───┴───┴───┴───┴───┴───┘

In view of (1), we have 1 = [0th] as well:

       ┌───┬───┬───┬───┬───┬───┐
       │5th│4th│3rd│2nd│1st│ 0■│▒
       ╞═══╪═══╪═══╪═══╪═══╪═══╡▒
       │ 2 │   │   │   │ 0 │   │▒
       ├───┼───┼───┼───┼───┼───┤▒
Step 3 │ 2 │   │   │   │ 0 │ 1 │▒
       └───┴───┴───┴───┴───┴───┘▒
        ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒

--- Idle ---
┌───┬───┬───┬───┬───┬───┐
│   │   │ 5 │   │ 3 │ 4 │
└───┴───┴───┴───┴───┴───┘

There is only one way to match ✅「⟨⋯ Perm(0,1,5) ⋯⟩」:

       ┌───┬───┬───┬───┬───┬───┐
       │5th│4th│3rd│ 2■│1st│0th│▒
       ╞═══╪═══╪═══╪═══╪═══╪═══╡▒
       │ 2 │   │   │   │ 0 │ 1 │▒
       ├───┼───┼───┼───┼───┼───┤▒
Step 4 │ 2 │   │   │ 5 │ 0 │ 1 │▒
       └───┴───┴───┴───┴───┴───┘▒
        ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒

--- Idle ---
┌───┬───┬───┬───┬───┬───┐
│   │   │   │   │ 3 │ 4 │
└───┴───┴───┴───┴───┴───┘

Finally, to match ✅「min ⊢4⊣ ≤ 2」, we finish by

       ┌───┬───┬───┬───┬───┬───┐
       │5th│ 4■│ 3■│2nd│1st│0th│▒
       ╞═══╪═══╪═══╪═══╪═══╪═══╡▒
       │ 2 │   │   │ 5 │ 0 │ 1 │▒
       ├───┼───┼───┼───┼───┼───┤▒
Step 5 │ 2 │ 4 │   │ 5 │ 0 │ 1 │▒
       ├───┼───┼───┼───┼───┼───┤▒
Step 6 │ 2 │ 4 │ 3 │ 5 │ 0 │ 1 │▒
       └───┴───┴───┴───┴───┴───┘▒
        ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒

--- Idle ---
┌───┬───┬───┬───┬───┬───┐
│   │   │   │   │   │   │
└───┴───┴───┴───┴───┴───┘

Q.E.D.

#125034_v2.11