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%I #26 Jan 29 2024 10:59:31
%S 1,1,1,16,900,5620,15022,134232,8215633,1062549091,129577107261
%N Number of maximal independent vertex sets in the n X n zebra graph.
%H Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/Matching.html">Matching</a>.
%H Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/MaximalIndependentVertexSet.html">Maximal Independent Vertex Set</a>.
%H Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/ZebraGraph.html">Zebra Graph</a>.
%t Table[Length@FindIndependentVertexSet[RelationGraph[Sort[Abs[Subtract[##]]] == {2, 3} &, Tuples[Range[n], 2]], Infinity, All], {n, 8}]
%o (Python)
%o from networkx import empty_graph, complement, find_cliques
%o def A367089(n):
%o G = empty_graph((i,j) for i in range(n) for j in range(n))
%o G.add_edges_from(((i,j),(i+k,j+l)) for i in range(n) for j in range(n) for (k,l) in ((2,3),(2,-3),(-2,3),(-2,-3),(3,2),(3,-2),(-3,2),(-3,-2)) if 0<=i+k<n and 0<=j+l<n)
%o return sum(1 for c in find_cliques(complement(G))) # _Chai Wah Wu_, Jan 27 2024
%K nonn,more
%O 1,4
%A _Eric W. Weisstein_, Jan 26 2024
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