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%I #27 Jan 26 2024 10:14:36
%S 1,2,6,42,220,3644,62272,1794762,83280570,6210321492
%N Number of maximal independent vertex sets in the n X n torus grid graph.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/MaximalIndependentVertexSet.html">Maximal Independent Vertex Set</a>.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/TorusGridGraph.html">Torus Grid Graph</a>.
%t Table[Length@FindIndependentVertexSet[GraphProduct[CycleGraph[n], CycleGraph[n], "Cartesian"], Infinity, All], {n, 3, 8}] (* _Eric W. Weisstein_, Jan 26 2024 *)
%o (Python)
%o from networkx import find_cliques, complement, cartesian_product, cycle_graph
%o def A321250(n): return sum(1 for c in find_cliques(complement(cartesian_product(cycle_graph(n),cycle_graph(n))))) # _Chai Wah Wu_, Jan 11 2024
%Y Cf. A027683.
%K nonn,more
%O 1,2
%A _Eric W. Weisstein_, Nov 01 2018
%E a(1), a(2), and a(10) from _Andrew Howroyd_, Nov 01 2018