1, six-sided palindrome formula: u', d, f', b, l, r', u', d.
2. Symmetric chessboard formula: L2, R2, F2, B2, U2, D2.
3. Hexagon Cross Equation 2: B2, F, L2, R2, D2, B2, F2, L2, R2, U2, F.
Rubik's cube development history
1970 In March, Larry Nichols invented the "jigsaw puzzle with rotating pieces in groups" and applied for a Canadian patent. It is a 2×2×2 Rubik's Cube, but each Rubik's Cube is attracted by magnets. 1972 obtained the American patent, two years earlier than Professor Rubik's Cube.
Rubik Arne is a professor of architecture and sculpture in Hungary. In order to help students understand the composition and structure of the space cube, he made the first prototype of the Rubik's Cube, inspired by the sand in the Danube.
1974, Professor rubik invented the first Rubik's Cube (then called Rubik's Cube), and obtained the Hungarian patent number HU 170062 in 1975, but did not apply for an international patent.
The first Rubik's Cube was sold in a toy store in Budapest in 1977. Unlike Nichols' Rubik's Cube, Professor Rubik's Cube's parts are interlocking like tenons, which are not easily separated by external forces and can be made of any material.