Designs, Codes and Cryptography

, Volume 37, Issue 2, pp 347–353 | Cite as

Non Existence of Triangle Free Quasi-symmetric Designs

  • Rajendra M. Pawale


The following two results are proved. Let D be a triangle free quasi-symmetric design with k=2yx and x≥ 1 then D is a trivial design with v=5 and k=3. There do no exist triangle free quasi-symmetric designs with x≥ 1 and λ=y or λ=y−1.


Quasi-symmetric designs strongly regular graphs 

AMS Classification:

Primary 05 B05 Secondary 05 B30 05 B25 


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Copyright information

© Springer Science+Business Media, Inc. 2005

Authors and Affiliations

  1. 1.Sathaye CollegeMumbaiIndia

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