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%I #23 Jan 29 2024 14:23:12
%S 1,1,1,1,16,1540,176460,6332072,81841692,2434154301,124866787929
%N Number of maximal independent vertex sets in the n X n fiveleaper graph.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/FiveleaperGraph.html">Fiveleaper Graph</a>.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/MaximalIndependentVertexSet.html">Maximal Independent Vertex Set</a>.
%t Table[Length@FindIndependentVertexSet[RelationGraph[EuclideanDistance[##] == 5 &, Tuples[Range[n], 2]], Infinity, All], {n, 8}]
%o (Python)
%o from networkx import empty_graph, find_cliques, complement
%o def A321247(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 ((5,0),(-5,0),(0,5),(0,-5),(3,4),(3,-4),(-3,4),(-3,-4),(4,3),(4,-3),(-4,3),(-4,-3)) 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 11 2024
%K nonn,more
%O 1,5
%A _Eric W. Weisstein_, Nov 01 2018
%E a(10) from _Chai Wah Wu_, Jan 17 2024
%E a(11) from _Eric W. Weisstein_, Jan 29 2024
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