Latest Records for the Snake-in-the-Box Problem (December, 2006)

Snakes (aka: open snakes)

Dimension

Length

Source

1 1* -
2 2* (2)
3 4* (2)
4 7* (2)
5 13* (2)
6 26* (2)
7 50* (6)
8 97 (7)
9 188 (8)
10 363 (8)
11 680 (1)
12 1260 (1)

Coils (aka: closed snakes)

Dimension

Length

Source

1 0* -
2 4* (3)
3 6* (3)
4 8* (3)
5 14* (3)
6 26* (3)
7 48* (4)
8 96 (5)
9 180 (1)
10 344 (1)
11 630 (1)
12 1238 (5)

* denotes absolute bound.

References:

**1** Casella, D.A. and W.D. Potter, "Using Evolutionary Techniques to Hunt for Snakes and Coils". Proceedings of the 2005 IEEE Congress on Evolutionary Computing, Edinburgh, Scotland, September, 2005.
**2** Davies, D.W., "Longest 'separated' paths and loops in an N-cube", IEEE Trans. Electron. Comput EC-14 (1965) 261.
**3** Kautz, W.H., "Unit-Distance Error-Checking Codes", IRE Transactions on Electronic Computers, Vol EC-7, (1958) 179-180.
**4** Kochut, K.J., "Snake-in-the-Box Codes for Dimension 7.", Journal of Combinatorial Mathematics and Combinatorial Computing 20 (1998) 175--185.
**5** Paterson, K.G. and J. Tuliani, "Some New Circuit Codes", IEEE Transactions on Information Theory, Vol. 44, No. 3, 1305-1309 (1998).
**6** Potter, W.D., R.W. Robinson, J.A. Miller and K.J. Kochut, "Using the Genetic Algorithm to find Snake-in-the-Box Codes", Proceedings of the 7th International Conference on Industrial & Engineering Applications of Artificial Intelligence and Expert Systems (1994) 307-314.
**7** Rajan, D.S. and A.M. Shende, "Maximal and Reversible Snakes in Hypercubes", 24th Annual Australasian Conference on Combinatorial Mathematics and Combinatorial Computation (1999).
**8** Tuohy, D.R., W.D. Potter and D.A. Casella, "Searching for Snake-in-the-Box Codes with Evolved Pruning Models", Proceedings of the 2007 Int. Conf. on Genetic and Evolutionary Methods (GEM'2007), 3-9.

 

updated 7/30/2007.