A039927 - OEIS

A039927

Number of types of maximal mixed orthogonal arrays with n runs.

0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 4, 1, 1, 1, 2, 1, 2, 1, 4, 1, 1, 1

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OFFSET

1,12

COMMENTS

Number of dual atoms in lattice of parameters of mixed orthogonal arrays with n runs and strength 2.

a(36) is the first unknown term.

REFERENCES

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

LINKS

Table of n, a(n) for n=1..23.

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 (Abstract, pdf, ps).

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.

CROSSREFS

Cf. A039930, A039931.

Sequence in context: A181873 A229293 A269443 * A336722 A073802 A132157

Adjacent sequences: A039924 A039925 A039926 * A039928 A039929 A039930

KEYWORD

nonn,nice,more

AUTHOR

N. J. A. Sloane

EXTENSIONS

Needs to be updated using the results of Schoen et al. (2010). - N. J. A. Sloane, Feb 21 2013

STATUS

approved