Alexander's star
Alexander's Star is similar to the Rubik's Cube (also known as " Rubik's Cube ") is a 3D puzzle game , but in comparison to this hexahedron (cube) with 20 moving parts in the form of a great dodecahedron with 30 moving parts and therefore more closely resembles the Megaminx . The maximum diameter of two opposing tips is 101.6 mm (4 ″ ), the edge lengths each around 49 mm.
He is the brainchild of Adam Alexander, a New York mathematician and inventor. Registered for a patent in 1982, however, it never came close to the popularity of the Rubik's Cube.
Each of the twelve pentagonal faces running into one another is also the plane of rotation of a raised star in the shape of a pentagram , so it has five permissible (covering) rotary positions. In terms of color, the Alexander's Star is designed in such a way that each of the twelve rotating stars has 2 × 5 colors and the respective level has the sixth, the same as the spatially exactly opposite surface on the other side.
Not all 29! · 2 13 = 72,431,714,252,715,638,411,621,302,272,000,000 or ≈ 7.24 · 10 34 positions can be set or differentiated due to the symmetry, 30 are theoretically possible! · 2 30 permutations .
literature
- Adam Alexander: Official Solution to Alexander's Star Puzzle. 1982, ISBN 978-0-345-30842-9 (paperback, English).