Notes on the “15” Puzzle¶
Johnson, W. W., & Story, W. E. (1879). Notes on the “15” Puzzle. American Journal of Mathematics, 2(4), 397-404.
Cited by¶
1 citation across 1 artifact.
Each citation links to the sentence it supports in the citing article.
Mechanisms¶
- Localized Defect Glide Method
- The sliding puzzle makes this concrete — exactly half of all tile arrangements can never be reached from a given start, because a parity invariant is conserved by every legal slide.
This sourceProves that legal moves preserve a parity class in the 15-puzzle, so only half of all arrangements are reachable from a fixed start.
- The sliding puzzle makes this concrete — exactly half of all tile arrangements can never be reached from a given start, because a parity invariant is conserved by every legal slide.
Verification¶
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Does it back the claim? Not recorded. The single citation of this work carries no recorded support check.
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Registry ID ref:a87f6358da59 · see in the full table