How to solve ANY slide puzzle regardless of its size – Kaplof
Math302: 15-Puzzle
Sliding Block Puzzles, Part 3 | Random(Blog)
15 puzzle - Wikipedia
How to check if an instance of 15 puzzle is solvable? - GeeksforGeeks
Rush Hour puzzle solver and generator | FlowingData
CS61C Fall 2014 Project 2
GitHub - alexyuisingwu/sliding-puzzle-solver: A web app that allows users to create, play, generate and visualize optimal solutions for sliding puzzles with custom images and dimensions.