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%I #12 Jun 14 2021 03:12:23
%S 0,2,0,3,0,0,6,0,0,10,0,0,9,2,0,0,0,14,0,0,0,8,6,0,0,0,3,27,0,0,0,0,
%T 60,2,0,0,0,0,33,33,0,0,0,0,9,84,6,0,0,0,0,0,91,52,0,0,0,0,0,14,196,2,
%U 0,0,0,0,0,3,280,60,0,0,0,0,0,0,200,272,6
%N Irregular triangle read by rows: number of maximal irredundant sets of size k in the n-cycle graph.
%C For each row, k lies in the range 0..floor(n/2). The upper end of the range is the upper irredundance number of the graph.
%H Andrew Howroyd, <a href="/A291044/b291044.txt">Table of n, a(n) for n = 2..991</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/CycleGraph.html">Cycle Graph</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/IrredundantSet.html">Irredundant Set</a>
%F T(n,k) = 0 for k < ceiling(n/3).
%F Sum_{k=0..floor(n/2)} T(n,k) = A286954(n). - _Eric W. Weisstein_, Jun 11 2021
%e Triangle begins:
%e 0, 2;
%e 0, 3;
%e 0, 0, 6;
%e 0, 0, 10;
%e 0, 0, 9 2;
%e 0, 0, 0, 14;
%e 0, 0, 0, 8, 6;
%e 0, 0, 0, 3, 27;
%e 0, 0, 0, 0, 60, 2;
%e 0, 0, 0, 0, 33, 33;
%e 0, 0, 0, 0, 9, 84, 6;
%e 0, 0, 0, 0, 0, 91, 52;
%e 0, 0, 0, 0, 0, 14, 196, 2;
%e ...
%e As polynomials these are 2*x; 3*x; 6*x^2; 10*x^2; 9*x^2 + 2*x^3; etc.
%Y Row sums are A286954.
%K nonn,tabf
%O 2,2
%A _Andrew Howroyd_, Aug 16 2017
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