

A079761


Number of positions that are exactly n moves from the starting position in the 2 X 2 X 2 Rubik cube puzzle.


4



1, 9, 54, 321, 1847, 9992, 50136, 227536, 870072, 1887748, 623800, 2644
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OFFSET

0,2


COMMENTS

This is the number of positions that can be reached in n moves from the start, but which cannot be reached in fewer than n moves.
A puzzle in the Rubik cube family. The total number of distinct positions is 3674160. A halfturn is considered to be one move.


REFERENCES

D. R. Hofstadter, Metamagical Themas, Basic Books, NY, 1985, p. 359.


LINKS

Table of n, a(n) for n=0..11.
Mark Longridge, God's Algorithm Calculations for Rubik's Cube...
Jaap Scherphuis, Puzzle Pages


CROSSREFS

Cf. A079762, A152169.
Sequence in context: A243415 A276602 A079764 * A115784 A037599 A037704
Adjacent sequences: A079758 A079759 A079760 * A079762 A079763 A079764


KEYWORD

nonn,fini,full


AUTHOR

N. J. A. Sloane, Feb 20 2003


STATUS

approved



