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%I #4 Mar 30 2012 16:49:52
%S 1,2,4,9,31,128
%N Number of nonisomorphic, constructed lattice-square designs of order n as n runs through the odd prime-powers (3, 5, 7, 9, 11, 13, ...).
%C Equivalence classes of designs are challenging. Here the difficulty is reduced by focusing on constructed designs.
%D W. Y.-C. Chen and D. C. Torney, Equivalence Classes of Matchings and Lattice-Square Designs, Discrete Applied Math, in press.
%H William Y.-C. Chen and David C. Torney, <a href="http://dx.doi.org/10.1016/j.dam.2004.02.013">Equivalence Classes of Matchings and Lattice-Square Designs</a>, Discr. Appl. Math. vol. 145 no. 3 (2005) pp 349-357.
%K nonn,uned,obsc
%O 3,2
%A David C. Torney (dtorney(AT)earthlink.com), Mar 17 2004
%E What does "constructed" mean? If, as I suspect, it means constructed as of Mar 17 2004, then this is a time-dependent sequence and does not belong in the OEIS. - _N. J. A. Sloane_, Mar 18 2004