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  "body": "\n## Summary\n\nIn graph theory, the **Berlekamp–Van Lint–Seidel graph** is a locally linear strongly regular graph with parameters $(243,22,1,2)$. This means that it has 243 vertices, 22 edges per vertex (for a total of 2673 edges), exactly one shared neighbor per pair of adjacent vertices, and exactly two shared neighbors per pair of non-adjacent vertices. It was constructed by Elwyn Berlekamp, J. H. van Lint, and Johan Jacob Seidel as the coset graph of the ternary Golay code.\n",
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