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2026-04-07 WR

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

⟨ ⁵ᵗʰ▨ ⁴ᵗʰ▨ ³ʳᵈ▨ ²ⁿᵈ▨ ¹ˢᵗ▨ ⁰ᵗʰ▨ ⟩

✅Match
{p4, p3, p0} = ? + {0,1,2}
⟨⋯ a ⋯ 4 ⋯⟩, a = 1|5
5th → a, 1st → b, |a-b|=2

⛔Avoid
Jump(0,1) = 0
⟨     ³ʳᵈb   ¹ˢᵗa   ⟩, a > b
⟨     ³ʳᵈa     ⁰ᵗʰb ⟩, a > b

#125034_v2.12


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

Proof of 2026-04-07 WR
══════════════════════

Notation: if Nth -> a, then we write pN = a.

To match ✅「{p4, p3, p0} = ? + {0,1,2}」, we need p4, p3, p0 to be consecutive integers.

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

There are four possibilities for {p4, p3, p0}:

(A) {0,1,2} (idle: 3,4,5)
(B) {1,2,3} (idle: 0,4,5)
(C) {2,3,4} (idle: 0,1,5)
(D) {3,4,5} (idle: 0,1,2)

Observe that if it is (B) or (C), then we will fail to match ✅「5th → a, 1st → b, |a-b|=2」:

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

Therefore, it is (A) or (D). It is (D) indeed, for otherwise we will fail to avoid ⛔「⟨     ³ʳᵈb   ¹ˢᵗa   ⟩, a > b」.

As {p4, p3, p0} = {3,4,5}, we have

(1) {p5, p2, p1} = {0,1,2}.

To match ✅「5th → a, 1st → b, |a-b|=2」, we need

(2) {p5, p1} = {0,2}.

Combining (1) with (2), we get p2 = 1:

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

--- Idle ---
┌───┬───┬───┬───┬───┬───┐
│   │ 2 │ 5 │ 0 │ 3 │ 4 │
└───┴───┴───┴───┴───┴───┘

It then follows from (1) and ⛔「Jump(0,1) = 0」 that

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

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

Next, we consider where to place 4. If it is p4, then we cannot match ✅「⟨⋯ a ⋯ 4 ⋯⟩, a = 1|5」. Else if it is p3, then the preceding pattern implies

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

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

and we will fail to avoid ⛔「⟨     ³ʳᵈa     ⁰ᵗʰb ⟩, a > b」. Consequently, 4 = p0:

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

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

Finally, to avoid ⛔「⟨     ³ʳᵈa     ⁰ᵗʰb ⟩, a > b」, we finish by

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

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

Q.E.D.

#125034_v2.12