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 2160.
Table of n, a(n) for n=0..6.
Jaap Scherphuis, Puzzle Pages
Sequence in context: A073390 A069021 A079763 * A225977 A305782 A292536
Adjacent sequences: A079782 A079783 A079784 * A079786 A079787 A079788
N. J. A. Sloane, Feb 20 2003