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%I #8 Mar 06 2024 04:48:24
%S -1,0,6,384,29160,2949120,393750000,67722117120,14643516908160,
%T 3896394330931200,1252631480200531200,479001600000000000000,
%U 214973646592670930764800,111929817779497742421196800
%N a(n) = (n-2)^n*n!.
%C For n > 2, a(n) is the number of minimum vertex colorings of the n-sun graph.
%H Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/MinimumVertexColoring.html">Minimum Vertex Coloring</a>.
%H Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/SunGraph.html">Sun Graph</a>.
%t Table[(n - 2)^n n!, {n, 20}]
%K sign,easy
%O 1,3
%A _Eric W. Weisstein_, Mar 03 2024