The Strongly Regular (40, 12, 2, 4) Graphs

نویسنده

  • Edward Spence
چکیده

In a previous paper it was established that there are at least 27 non-isomorphic strongly regular (40, 12, 2, 4) graphs. Using a different and more efficient method we have re-investigated these graphs and have now been able to determine them all, and so complete the classification. We have discovered that there are precisely 28 non-isomorphic (40, 12, 2, 4) strongly regular graphs. The one that was not found in the previous investigation is characterised uniquely by the fact that every neighbour graph is triangle-free.

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عنوان ژورنال:
  • Electr. J. Comb.

دوره 7  شماره 

صفحات  -

تاریخ انتشار 2000