Rearrange the digits in ⟨125034⟩ to meet the rules below.
⟨ ⁵ᵗʰ▨ ⁴ᵗʰ▨ ³ʳᵈ▨ ²ⁿᵈ▨ ¹ˢᵗ▨ ⁰ᵗʰ▨ ⟩
✅Match
⟨⋯ 2 ⋯ 0 ⋯ 3 ⋯⟩
3rd → a, 0th → b, ab=15
{p5, p2, p1} = ? + {0,1,2}
⛔Avoid
⟨⋯ ᵃb ⋯⟩, a+b=7
#125034_v2.13
┌───┬───┬───┬───┬───┬───┐
│5th│4th│3rd│2nd│1st│0th│▒
╞═══╪═══╪═══╪═══╪═══╪═══╡▒
Step 1 │ │ 4 │ │ │ │ │▒
├───┼───┼───┼───┼───┼───┤▒
Step 2 │ │ 4 │ │ 2 │ │ │▒
├───┼───┼───┼───┼───┼───┤▒
Step 3 │ │ 4 │ │ 2 │ 0 │ │▒
├───┼───┼───┼───┼───┼───┤▒
Step 4 │ │ 4 │ │ 2 │ 0 │ 3 │▒
├───┼───┼───┼───┼───┼───┤▒
Step 5 │ │ 4 │ 5 │ 2 │ 0 │ 3 │▒
├───┼───┼───┼───┼───┼───┤▒
Step 6 │ 1 │ 4 │ 5 │ 2 │ 0 │ 3 │▒
└───┴───┴───┴───┴───┴───┘▒
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Proof of 2026-06-16 WR
══════════════════════
Notation: if nth -> a, then we write [nth] = a.
By ✅「3rd → a, 0th → b, ab=15」, we have
(1) {[3rd], [0th]} = {3,5}.
┌───┬───┬───┬───┬───┬───┐
│5th│4th│3rd│2nd│1st│0th│
╞═══╪═══╪═══╪═══╪═══╪═══╡
│ │ │3 5│ │ │3 5│
└───┴───┴───┴───┴───┴───┘
--- Idle ---
┌───┬───┬───┬───┬───┬───┐
│ 1 │ 2 │ │ 0 │ │ 4 │
└───┴───┴───┴───┴───┴───┘
Then, to match this and ✅「{p5, p2, p1} = ? + {0,1,2}」 at the same time, we need
(2) {p5, p2, p1} = {0,1,2}.
┌───┬───┬───┬───┬───┬───┐
│5th│4th│3rd│2nd│1st│0th│
╞═══╪═══╪═══╪═══╪═══╪═══╡
│012│ │3 5│012│012│3 5│
└───┴───┴───┴───┴───┴───┘
--- Idle ---
┌───┬───┬───┬───┬───┬───┐
│ │ │ │ │ │ 4 │
└───┴───┴───┴───┴───┴───┘
As a result, we have [4th] = 4.
┌───┬───┬───┬───┬───┬───┐
│5th│ 4■│3rd│2nd│1st│0th│
╞═══╪═══╪═══╪═══╪═══╪═══╡
│012│ 4 │3 5│012│012│3 5│
└───┴───┴───┴───┴───┴───┘
Next, consider where to place 2. To avoid ⛔「⟨⋯ ᵃb ⋯⟩, a+b=7」, we need 2 != [5th]. Combining this with ✅「⟨⋯ 2 ⋯ 0 ⋯ 3 ⋯⟩」, we get:
┌───┬───┬───┬───┬───┬───┐
│5th│4th│3rd│ 2■│ 1■│ 0■│▒
╞═══╪═══╪═══╪═══╪═══╪═══╡▒
│ │ 4 │ │ │ │ │▒
├───┼───┼───┼───┼───┼───┤▒
Step 2 │ │ 4 │ │ 2 │ │ │▒
├───┼───┼───┼───┼───┼───┤▒
Step 3 │ │ 4 │ │ 2 │ 0 │ │▒
├───┼───┼───┼───┼───┼───┤▒
Step 4 │ │ 4 │ │ 2 │ 0 │ 3 │▒
└───┴───┴───┴───┴───┴───┘▒
▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒
--- Idle ---
┌───┬───┬───┬───┬───┬───┐
│ 1 │ │ 5 │ │ │ │
└───┴───┴───┴───┴───┴───┘
Finally, using ✅「3rd → a, 0th → b, ab=15」, we finish by
┌───┬───┬───┬───┬───┬───┐
│ 5■│4th│ 3■│2nd│1st│0th│▒
╞═══╪═══╪═══╪═══╪═══╪═══╡▒
│ │ 4 │ │ 2 │ 0 │ 3 │▒
├───┼───┼───┼───┼───┼───┤▒
Step 5 │ │ 4 │ 5 │ 2 │ 0 │ 3 │▒
├───┼───┼───┼───┼───┼───┤▒
Step 6 │ 1 │ 4 │ 5 │ 2 │ 0 │ 3 │▒
└───┴───┴───┴───┴───┴───┘▒
▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒
--- Idle ---
┌───┬───┬───┬───┬───┬───┐
│ │ │ │ │ │ │
└───┴───┴───┴───┴───┴───┘
Q.E.D.
#125034_v2.13