A367457 - OEIS

%I #25 Jan 27 2024 18:52:03

%S 1,1,1,25,300,4761,37908,1408969,42742245,1650878161,240427884762,

%T 14943334966921,4986511832627632,793446864376246336,

%U 451148370226544277049

%N Number of maximal independent vertex sets in the n X n camel graph.

%H Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/CamelGraph.html">Camel Graph</a>.

%H Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/MaximalIndependentVertexSet.html">Maximal Independent Vertex Set</a>.

%t Table[Length@FindIndependentVertexSet[RelationGraph[Sort[Abs[Subtract[##]]] == {1, 3} &, Tuples[Range[n], 2]], Infinity, All], {n, 8}]

%o (Python)

%o from networkx import empty_graph, complement, find_cliques

%o def A367457(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 ((1,3),(1,-3),(-1,3),(-1,-3),(3,1),(3,-1),(-3,1),(-3,-1)) 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