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  "body": "\n## Definition\n\nLet $G = (V, E)$ be a [[graph|0JD5C82QMB]].\nThe complement of $G$ is the graph $\\overline{G}$ with vertex set $V$.\nTwo distinct vertices are adjacent in $\\overline{G}$ if and only if they are not adjacent in $G$.\n\n## Remarks\n\nThe complement of the complement of $G$ is $G$.\nThe complement of the complete graph $K_n$ is the graph on $n$ vertices with no edges.\nA [[clique|0G52BPNPKG]] of $G$ is an [[independent set|0KZJ82WEPP]] of $\\overline{G}$. This links Ramsey numbers to colourings of $K_n$.\n\n## Explanations\n\n### L1 human\n\nTo get the complement, remove all edges of the graph and draw all the missing ones.\nIf $G$ records which people know each other, then $\\overline{G}$ records which people are strangers.\n",
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