Recreational Mathematics
Beast Number
http://mathworld.wolfram.com/BeastNumber.html
Hardy-Ramanujan Number
http://mathworld.wolfram.com/Hardy-RamanujanNumber.html
Tangram
https://mathworld.wolfram.com/Tangram.html
Magic Square
https://mathworld.wolfram.com/MagicSquare.html
Pythagorean Square Puzzle
https://mathworld.wolfram.com/PythagoreanSquarePuzzle.html
Tic-Tac-Toe
https://mathworld.wolfram.com/Tic-Tac-Toe.html
Chess
https://mathworld.wolfram.com/Chess.html
Go
https://mathworld.wolfram.com/Go.html
Poker
https://mathworld.wolfram.com/Poker.html
Dice
https://mathworld.wolfram.com/Dice.html
Bowling
https://mathworld.wolfram.com/Bowling.html
Icosian Game
https://mathworld.wolfram.com/IcosianGame.html
Maze
https://mathworld.wolfram.com/Maze.html
String Figure
https://mathworld.wolfram.com/StringFigure.html
Illusions
Ambihelical Hexnut
https://mathworld.wolfram.com/AmbihelicalHexnut.html
Angle Illusions
https://mathworld.wolfram.com/AngleIllusions.html
Benham’s Wheel
https://mathworld.wolfram.com/BenhamsWheel.html
Bullseye Illusion
https://mathworld.wolfram.com/BullseyeIllusion.html
Café Wall Illusion
https://mathworld.wolfram.com/CafeWallIllusion.html
Continuous Line Illusion
https://mathworld.wolfram.com/ContinuousLineIllusion.html
Delboeuf Illusion
https://mathworld.wolfram.com/DelboeufIllusion.html
Ehrenstein Illusion
https://mathworld.wolfram.com/EhrensteinIllusion.html
Fraser’s Spiral
https://mathworld.wolfram.com/FrasersSpiral.html
Freemish Crate
https://mathworld.wolfram.com/FreemishCrate.html
Goblet Illusion
https://mathworld.wolfram.com/GobletIllusion.html
Hering Illusion
https://mathworld.wolfram.com/HeringIllusion.html
Illusory Contour Figures
https://mathworld.wolfram.com/IllusoryContourFigures.html
Impossible Fork
https://mathworld.wolfram.com/ImpossibleFork.html