A079742 Number of positions that are exactly n moves from the starting position in the Roundy puzzle.

1, 6, 27, 114, 350, 879, 1069, 398, 35, 1

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 2880. Here we count quarter-turn moves. There is only one position that needs 9 quarter turns, the position with all the pieces flipped.

Links

Table of n, a(n) for n=0..9.

Jaap Scherphuis, Puzzle Pages

Crossrefs

Cf. A079817.

Sequence in context: A014825 A141844 A176476 * A291232 A171475 A130019

Adjacent sequences: A079739 A079740 A079741 * A079743 A079744 A079745

Keyword

nonn,fini,full

Author

N. J. A. Sloane, Feb 20 2003

Status

approved