OFFSET
0,5
REFERENCES
Ryskov, S. S., C-types of n-dimensional parallelohedra, Dokl. Akad. Nauk SSSR 212 (1973), 46-49.
Ryskov, S. S. and Baranovskii, E. P., C-types of n-dimensional lattices and 5-dimensional primitive parallelohedra (with application to the theory of coverings), Trudy Mat. Inst. Steklov 137 (1976). English translation: Proc. Steklov Inst. Math. 1978, no. 4, 140 pp.
CROSSREFS
KEYWORD
nonn,hard,nice
AUTHOR
N. J. A. Sloane, following a suggestion of J. H. Conway, Dec 26, 2003
STATUS
approved