Search: id:A006226 Results 1-1 of 1 results found. %I A006226 M1916 %S A006226 1,2,9,18,118,239,1594 %N A006226 Number of abstract n-dimensional crystallographic point groups. %D A006226 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %D A006226 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. %D A006226 A. C. Hurley, Finite rotation groups and crystal classes in four dimensions. Proc. Cambridge Philos. Soc. 47, (1951). 650-661. %D A006226 A. C. Hurley, Crystal Classes of Four-Dimensional Space R4, Acta Crystallog., 22 (1967), see especially p. 605. %D A006226 T. Janssen, Crystallographic Groups. North-Holland, Amsterdam, 1973, p. 73. %D A006226 W. Plesken and T. Schulz, Counting crystallographic groups in low dimensions, Experimental Mathematics, 9 (No. 3, 2000), 407-411. %H A006226 W. Plesken and T. Schulz, CARAT Homepage %H A006226 Experimental Mathematics, Home Page %Y A006226 Cf. A004027, A004028, A004029. %Y A006226 Sequence in context: A037421 A083423 A068978 this_sequence A109298 A075537 A075340 %Y A006226 Adjacent sequences: A006223 A006224 A006225 this_sequence A006227 A006228 A006229 %K A006226 hard,nonn,nice %O A006226 1,2 %A A006226 N. J. A. Sloane (njas(AT)research.att.com). %E A006226 Two more terms from W. Plesken and T. Schulz (tilman(AT)momo.math.rwth-aachen.de), Feb 27, 2001. Search completed in 0.001 seconds