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Demicaps in AG(4,3) and Maximal Cap Partitions

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Abstract

In this paper, we introduce a fundamental substructure of maximal caps in the affine geometry AG(4, 3) that we call demicaps. Demicaps provide a direct link to particular partitions of AG(4, 3) into 4 maximal caps plus a single point. The full collection of 36 maximal caps that are in exactly one partition with a given cap C can be expressed as unions of two disjoint demicaps taken from a set of 12 demicaps; these 12 can also be found using demicaps in C. The action of the affine group on these 36 maximal caps includes actions related to the outer automorphisms of \(S_6\).

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Notes

  1. The lines in a \(3\times 3\) subgrid, also called a plane, are three points horizontally, vertically, or diagonally, including diagonals as on a torus; the points in all other lines appear in three subgrids that are in the same position as a line in the \(3\times 3\) subgrids, so that, when the three subgrids are superimposed, those points either lie on top of one another, or they are in the same positions as a line in a subgrid. See Fig. 1.

References

  1. Awan, J.: Cap builder. http://webbox.lafayette.edu/mcmahone/capbuilder.html

  2. Bierbrauer, J.: Large caps. J. Geom. 76(1–2), 16–51 (2003). (Combinatorics, 2002 (Maratea))

    Article  MathSciNet  MATH  Google Scholar 

  3. Benjamin Lent Davis and Diane Maclagan: The card game SET. Math. Intell. 25(3), 33–40 (2003)

    Article  MathSciNet  MATH  Google Scholar 

  4. Edel, Y., Ferret, S., Landjev, I., Storme, L.: The classification of the largest caps in \(\rm AG(5,3)\). J. Combin. Theory Ser. A 99(1), 95–110 (2002)

    Article  MathSciNet  MATH  Google Scholar 

  5. Ellenberg, J.S., Gijswijt, D.: On large subsets of \(F^n_q\) with no three-term arithmetic progression. Ann. Math. Second Ser. 185(1), 339–343 (2017)

    Article  MATH  Google Scholar 

  6. Follett, M., Kalail, K., McMahon, E., Pelland, C., Won, R.: Partitions of \(AG(4,3)\) into maximal caps. Discret. Math. 337, 1–8 (2014)

    Article  MathSciNet  MATH  Google Scholar 

  7. Hill, R.: On Pellegrino’s $20$-caps in \(S_{4,3}\). In: Combinatorics ’81 (Rome, 1981), vol. 78: North-Holland Math. Stud., pp. 433–447. North-Holland, Amsterdam (1983)

  8. Kestenband, B.C.: Partitions of finite affine geometries into caps. Linear Multilinear Algebra 14(3), 257–270 (1983)

    Article  MathSciNet  MATH  Google Scholar 

  9. Pellegrino, G.: Sul massimo ordine delle calotte in S4,3. Matematiche (Catania) 25(149–157), 1970 (1971)

    MathSciNet  Google Scholar 

  10. Potechin, A.: Maximal caps in AG (6,3). Des. Codes Cryptogr. 46(3), 243–259 (2008)

    Article  MathSciNet  MATH  Google Scholar 

  11. Rotman, J.J.: An Introduction to the Theory of Groups. Graduate Texts in Mathematics, vol. 148, 4th edn. Springer, New York (1995)

    Book  MATH  Google Scholar 

  12. Wolfram Research, Inc: Mathematica, Version 11.3. Champaign, IL (2018)

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Research supported by NSF grant DMS-1063070.

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Correspondence to Elizabeth McMahon.

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Awan, J., Frechette, C., Li, Y. et al. Demicaps in AG(4,3) and Maximal Cap Partitions. Graphs and Combinatorics 38, 193 (2022). https://doi.org/10.1007/s00373-022-02568-x

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  • DOI: https://doi.org/10.1007/s00373-022-02568-x

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