login
This site is supported by donations to The OEIS Foundation.

 

Logo

Many excellent designs for a new banner were submitted. We will use the best of them in rotation.

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A006227 Number of n-dimensional space groups (including enantiomorphs).
(Formerly M2104)
2
1, 2, 17, 230, 4895 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

REFERENCES

H. Brown, R. B\"{u}low, J. Neub\"{u}ser, H. Wondratschek and H. Zassenhaus, Crystallographic Groups of Four-Dimensional Space. Wiley, NY, 1978, p. 52.

P. Engel, ``Geometric crystallography,'' in P. M. Gruber and J. M. Wills, editors, Handbook of Convex Geometry. North-Holland, Amsterdam, Vol. B, pp. 989-1041.

J. E. Goodman and J. O'Rourke, editors, Handbook of Discrete and Computational Geometry, CRC Press, 1997, p. 102.

T. Janssen, Crystallographic Groups. North-Holland, Amsterdam, 1973, p. 119.

W. Plesken and T. Schulz, Counting crystallographic groups in low dimensions, Experimental Mathematics, 9 (No. 3, 2000), 407-411.

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..4.

Dror Bar-Natan, Illustrations of 2-dimensional symmetry groups

W. Plesken and T. Schulz, CARAT Homepage

Experimental Mathematics, Home Page

CROSSREFS

Cf. A004029.

Sequence in context: A144208 A183711 A058239 * A036082 A099694 A218681

Adjacent sequences:  A006224 A006225 A006226 * A006228 A006229 A006230

KEYWORD

nonn,hard,nice

AUTHOR

N. J. A. Sloane.

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified April 17 03:13 EDT 2014. Contains 240628 sequences.