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Designs, Codes and Cryptography

, Volume 40, Issue 2, pp 187–190 | Cite as

There are 1239 Steiner Triple Systems STS(31) of 2-rank 27

  • Octavio Páez OsunaEmail author
Article

Abstract

A computer search over the words of weight 3 in the code of blocks of a classical Steiner triple system (STS) on 31 points is carried out to classify all STS(31) whose incidence matrix has 2-rank equal to 27, one more than the possible minimum of 26. There is a total of 1239 nonisomorphic STS(31) of 2-rank 27.

Keywords

Steiner triple system of 2-rank 27 Block code of a design Backtracking search with isomorph rejection 

AMS Classification

05B07 

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Copyright information

© Springer Science+Business Media, LLC 2006

Authors and Affiliations

  1. 1.Departamento de MatemáticasFacultad de Ciencias, UNAMMéxico

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