## FORBIDDEN-MINOR CHARACTERIZATION FOR THE CLASS OF COGRAPHIC ELEMENT SPLITTING MATROIDS

 Kiran Dalvi Department of Mathematics Government College of Engineering Pune 411 005 India e-mail: kiran_dalvi111@yahoo.com Y.M. Borse  and  M.M. Shikare Department of Mathematics University of Pune Pune 411 007 India e-mail:ymborse11@gmail.com e-mail:mms@math.unipune.ernet.in

## Abstract

In this paper, we prove that an element splitting operation by every pair of elements on a cographic matroid yields a cographic matroid if and only if it has no minor isomorphic to M(K4).

Keywords: binary matroid, graphic matroid, cographic matroid, minor.

2010 Mathematics Subject Classifications: 05B35.

## References

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Received 14 January 2009
Revised 16 June 2010
Accepted 16 June 2010