Chute Remote Pair

A Chute Remote Pair occurs when two bi-value cells with identical candidates exist in the same chute but cannot see each other. By examining the third box in that chute, specific candidates can be eliminated.

What's a Chute?

A chute is a subdivision of the grid containing three boxes in a line:

How It Works

The Pattern

Look for two bi-value cells in the same chute where:

The Third Box Rule

Examine the cells in the third box (the one containing neither remote pair cell):

The Logic

Consider two cells both containing {A, B} as a remote pair:

How to Spot Chute Remote Pairs

Chute Focus

The key to spotting Chute Remote Pairs is understanding chutes — groups of three boxes in a line:

Step Action What to Look For
1 Identify chutes 3 bands (horizontal) + 3 stacks (vertical) = 6 chutes
2 Find matching bi-value cells Two cells with identical candidates in same chute
3 Verify non-visibility Cells must NOT see each other (different row, column, box)
4 Check third box Which candidates appear in the third box?
5 Determine elimination Based on third box analysis

Step-by-Step Scanning

  1. Scan for bi-value pairs — Find cells with exactly two identical candidates
  2. Check chute membership — Are both cells in the same band or stack?
  3. Verify they don't see each other — Must be in different rows, columns, AND boxes
  4. Examine third box — Look at the third box in that chute
  5. Apply third box rule — If only one candidate appears → eliminate from cells seeing both

The Third Box Rule

Third Box Contains Elimination
Only A (not B) Eliminate A from cells seeing both remote pair cells
Only B (not A) Eliminate B from cells seeing both remote pair cells
Both A and B No eliminations possible
Neither A nor B Eliminate both (rare)

Example

Look for bi-value cells in the same chute and ask: do they form a remote pair?

Pattern Analysis:

puzzle: S9B2J0B5V0962050F2I0C0I5U0E560C566201022I060C0A644C62050I03095U4A054C2D062B0E5U0F03440A0I2C040L040L0G060I0C08052C032C0E4A560R091F08050I1M010C2K2K360F0A0D020I070E0C0H
mode: guided
technique: Chute Remote Pair
initial:
  layers:
    hints: true
steps:
  - text: >
      Look for bi-value cells with identical candidates. R1C8 and R3C1 both have {4, 7}.
    hint: subtle
    technique: CRP
    state:
      selection:
        cells: [R1C8, R3C1]

  - text: >
      These cells are in the same band (band 1) but different boxes (box 3 and box 1). They cannot see each other!
    hint: obvious
    technique: CRP
    state:
      selection:
        cells: [R1C8, R3C1]

  - text: >
      Check the third box (box 2). The unused cells R2C4, R2C5, R2C6 contain only candidate 4 — not 7.
    hint: obvious
    technique: CRP
    state:
      selection:
        cells: [R2C4, R2C5, R2C6]

  - text: >
      Since only 4 appears in box 2, eliminate 4 from cells seeing both remote pair cells: R1C1~4 and R3C7~4.
    hint: detailed
    technique: CRP
    state:
      selection:
        cells: [R1C1, R3C7]
settings:
  showCandidates: true
  showControls: true
  showDescription: true
  navigation: numbered

Example 2: Solved Cells in the Third Box

The third box rule applies to all cells in the box — including solved cells! This example shows how solved values participate in the pattern.

Pattern Analysis:

puzzle: S9B0C05AI8I0H0B7U019E7V7U8R050703BG1OB89E02088I0D0103360E06D69Q020Z9UB72ECZD0019G0D0C9EC405DW0E9E9K2B06087P2G040L0F05080L0D07090C65622L0C09060E0S0L7X037X2B112Q1P081H
mode: guided
technique: Chute Remote Pair
initial:
  layers:
    hints: true
steps:
  - text: >
      Look for bi-value cells with identical candidates. R1C9 and R3C1 both have {7, 9}.
    hint: subtle
    technique: CRP
    state:
      selection:
        cells: [R1C9, R3C1]

  - text: >
      Both cells are in band 1 but different boxes (box 3 and box 1). They cannot see each other — this is a remote pair!
    hint: obvious
    technique: CRP
    state:
      selection:
        cells: [R1C9, R3C1]

  - text: >
      Check the third box (box 2). The cells R2C4=5, R2C5=7, R2C6=3 are all solved. The solved 7 counts as candidate 7 being present!
    hint: obvious
    technique: CRP
    state:
      selection:
        cells: [R2C4, R2C5, R2C6]

  - text: >
      Since 7 appears in box 2 (as a solved value), eliminate 7 from cells seeing both remote pair cells: R1C3~7 and R3C8~7.
    hint: detailed
    technique: CRP
    state:
      selection:
        cells: [R1C3, R3C8]
settings:
  showCandidates: true
  showControls: true
  showDescription: true
  navigation: numbered

Tips

  1. Scan chutes systematically — There are 6 chutes total (3 bands + 3 stacks)
  2. Look for bi-value pairs — Find cells with exactly two candidates
  3. Verify non-visibility — The cells must not see each other
  4. Check the third box — Count which candidates appear there (including solved cells!)

When to Use

Chute Remote Pairs typically appear in:

Related to Naked Pairs

Technique Scope Cells See Each Other? Eliminates From
Naked Pair Single unit Yes Other cells in unit
Chute Remote Pair Chute (3 boxes) No Cells seeing both

More Puzzles

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