

A006227


Number of ndimensional space groups (including enantiomorphs).
(Formerly M2104)


4




OFFSET

0,2


REFERENCES

H. Brown, R. Bülow, J. Neubüser, H. Wondratschek and H. Zassenhaus, Crystallographic Groups of FourDimensional Space. Wiley, NY, 1978, p. 52.
P. Engel, Geometric crystallography, in P. M. Gruber and J. M. Wills, editors, Handbook of Convex Geometry. NorthHolland, Amsterdam, Vol. B, pp. 9891041.
J. E. Goodman and J. O'Rourke, editors, Handbook of Discrete and Computational Geometry, CRC Press, 1997, p. 102.
T. Janssen, Crystallographic Groups. NorthHolland, Amsterdam, 1973, p. 119.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).


LINKS

Table of n, a(n) for n=0..5.
Dror BarNatan, Illustrations of 2dimensional symmetry groups
J. Neubüser, B. Souvignier and H. Wondratschek, Corrections to Crystallographic Groups of FourDimensional Space by Brown et al. (1978) [New York: Wiley and Sons], Acta Cryst., A58 (2002), 301.
J. Opgenorth, W. Plesken and T. Schulz, Crystallographic Algorithms and Tables, Acta Cryst., A54 (1998), 517531.
W. Plesken, J. Opgenorth and T. Schulz, CARAT  a package for mathematical crystallography, Journal of Applied Crystallography, 31 (1998), 827828.
W. Plesken and T. Schulz, CARAT Homepage
W. Plesken and T. Schulz, CARAT Homepage [Cached copy in pdf format (without subsidiary pages), with permission]
W. Plesken and T. Schulz, Introduction to CARAT [Cached copy in pdf format (without subsidiary pages), with permission]W. Plesken and T. Schulz, Counting crystallographic groups in low dimensions, Experimental Mathematics 9 (No. 3, 2000) 407411.
B. Souvignier, Enantiomorphism of crystallographic groups in higher dimensions with results in dimensions up to 6, Acta Cryst., A59 (2003), 210220.
The Fascination of Crystals and Symmetry, 230 (The space group list project)
Wikipedia, Space group


CROSSREFS

Cf. A004027, A004029.
Sequence in context: A144208 A183711 A058239 * A036082 A240999 A099694
Adjacent sequences: A006224 A006225 A006226 * A006228 A006229 A006230


KEYWORD

nonn,hard,nice


AUTHOR

N. J. A. Sloane


EXTENSIONS

a(4) corrected according to Neubüser, Souvignier and Wondratschek (2002)  Susanne Wienand, May 19 2014
a(5) added according to Souvignier (2003); a(6) should not be extracted from that paper because it uses the old incorrect CARAT data for d=6  Andrey Zabolotskiy, May 19 2015


STATUS

approved



