1,2

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.

A. C. Hurley, Finite rotation groups and crystal classes in four dimensions. Proc. Cambridge Philos. Soc. 47, (1951). 650-661.

A. C. Hurley, Crystal Classes of Four-Dimensional Space R4, Acta Crystallog., 22 (1967), see especially p. 605.

T. Janssen, Crystallographic Groups. North-Holland, Amsterdam, 1973, p. 73.

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

W. Plesken and T. Schulz, CARAT Homepage

Experimental Mathematics, Home Page

Cf. A004027, A004028, A004029.

Adjacent sequences: A006223 A006224 A006225 this_sequence A006227 A006228 A006229

Sequence in context: A037421 A083423 A068978 this_sequence A109298 A075537 A075340

hard,nonn,nice

njas

Two more terms from W. Plesken and T. Schulz (tilman(AT)momo.math.rwth-aachen.de), Feb 27, 2001.