A090034 Number of configurations of the 3 X 2 variant of Sam Loyd's sliding block 15-puzzle that require a minimum of n moves to be reached, starting with the empty square in one of the corners.

1, 2, 3, 5, 6, 7, 10, 12, 12, 16, 23, 25, 28, 39, 44, 40, 29, 21, 18, 12, 6, 1

Offset

0,2

Comments

Data from Karlemo and Östergård. See corresponding link in A087725.

References

See A087725.

Links

Table of n, a(n) for n=0..21.

Hugo Pfoertner, Solutions of small n*2 sliding block puzzles.

Takaken, n-Puzzle Page.

Takaken, No. 32 (5 puzzles).

Example

Starting with
123
45-
the most distant configuration corresponding to a(21)=1 is
45-
123 (i.e., it takes longest just to swap the two rows).

Prog

See link in A089473.
(Python) # alst(), moves(), swap() in A089473
print(alst("-12345", (3, 2))) # Michael S. Branicky, Dec 30 2020

Crossrefs

Cf. A087725, A089473, A090033, A090035, A090036, A090163, A090167.

Sequence in context: A031989 A023746 A357425 * A037016 A308981 A239746

Adjacent sequences: A090031 A090032 A090033 * A090035 A090036 A090037

Keyword

fini,full,nonn

Author

Hugo Pfoertner, Nov 23 2003

Status

approved