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 A039931 Number of different sets of parameters for mixed orthogonal arrays with n runs and strength 2. 2

%I

%S 1,2,2,5,2,5,2,14,6,5,2,23,2,5,5,61,2,26,2,35,5,5,2

%N Number of different sets of parameters for mixed orthogonal arrays with n runs and strength 2.

%D A. S. Hedayat, N. J. A. Sloane and J. Stufken, Orthogonal Arrays, Springer-Verlag, NY, 1999.

%D Eric D. Schoen, Pieter T. Eendebak and Man V. M. Nguyen, Complete enumeration of pure-level and mixed-level orthogonal arrays, Journal of Combinatorial Designs, Volume 18, Issue 2, pages 123-140, March 2010; DOI: 10.1002/jcd.20236; Correction: Journal of Combinatorial Designs, Volume 18, Issue 6, page 488, November 2010; DOI: 10.1002/jcd.20270.

%H E. M. Rains, N. J. A. Sloane and J. Stufken, The Lattice of N-Run Orthogonal Arrays, J. Stat. Planning Inference, 102 (2002), 477-500 (<a href="http://neilsloane.com/doc/rao.txt">Abstract</a>, <a href="http://neilsloane.com/doc/rao.pdf">pdf</a>, <a href="http://neilsloane.com/doc/rao.ps">ps</a>)

%e For 12 runs there are 23 different sets of parameters: 12^1, 2^k with 1<=k<=11, 3^1*2^k with 0<=k<=4, 6^1*2^k with 0<=k<=2, 4^1*3^1, 4^1 and 1^1.

%Y Cf. A039927, A039930.

%K nonn,nice,more

%O 1,2

%A _N. J. A. Sloane_.

%E Needs to be updated using the results of Schoen et al. (2010). - _N. J. A. Sloane_, Feb 21 2013

%E a(36) is the first unknown term.

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