THE RUBIK’S CUBE MATH AND TUTORIAL – MAXIMUM NUMBER OF MOVES TO SOLVE CUBES WITH N SQUARES

The Rubik’s Cube is a 3D mechanical puzzle invented by the Hungarian architect Ernő Rubik in 1974.

Rubik's Cube

Rubik’s Cube

Its original and simpler version (3×3) – that presents 9 squares on each of the 6 faces, with 54 squares totally – can assume up to 43.252.003.274.489.856.000 positions!

Nonetheless, every position of 3×3 Rubik’s Cube can be solved in 20 moves or less (named “God’s Number”), whereas the maximum number of moves required to solve a Rubik’s cube with N squares per row is proportional to N2/log N.

These two results were found respectively by the cuber Tomas Rokicki and his colleagues in 2010 and by the Erik Demaine‘s (Professor of Computer science and engineering at MIT) research team in 2011.

Finally, I suggest you to watch this tutorial video which explains how to solve a Rubik’s Cube in under a minute.

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SCIENCE DISCIPLINES ON THE WEB – A CLOUD ANALYSIS OF THE GOOGLE RESULTS OF ESSENTIAL SCIENCE INDICATORS SUBJECT AREAS

Have you ever wondered what is the most discussed science discipline on the Web? As far as I am concerned, yes, I have.

So, firstly, I looked for both a popular and influential classification of science disciplines.
Therefore, I considered the Essential Science Indicators Subject Areas classification and I loosely adapted it for quering on line, resulting in the following 26 clusters:

1) Agricultural Sciences
2) Biology
3) Biochemistry
4) Chemistry
5) Clinical Medicine
6) Computer Science
7) Economics
8) Engineering
9) Ecology
10) Geosciences
11) Immunology
12) Materials Science
13) Mathematics
14) Microbiology
15) Molecular Biology
16) Genetics
17) Neuroscience
18) Pharmacology
19) Physics
20) Plant Science
21) Animal Science
22) Psychiatry
23) Psychology
24) Social Sciences
25) Space science
26) Toxicology

Then, I made the analysis of the presence on Google search engine of those terms, and these are the results:

science disciplines cloud

science disciplines cloud

As you can see in the above cloud, “Engineering” is the most used word, followed at a distance by “Economics”, “Chemistry”, “Physics” and the other ones, until “Animal Science”, the loss employed term.