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%I #20 Oct 27 2017 10:52:42
%S 1,2,4,11,33,1,142,12,1,1,822,169,39,10,2,1,1,6966,3580,1241,378,120,
%T 36,16,5,2,1,1,79853,92850,59115,26667,10344,3666,1381,483,184,75,30,
%U 11,5,2,1,1
%N Triangle read by rows: T(n,k) is the number of graphs with n vertices and skewness k (n >= 1 and k >= 0).
%C The sum of the n-th row is equal to A000088(n).
%C Length of the n-th row kmax(n) is A000124(n-4) for n > 3 (conjectured).
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/GraphSkewness.html">Graph Skewness</a>
%F T(n,0) = A005470(n).
%F T(n,kmax(n)) = 1 for n > 4.
%F T(n,kmax(n)-1) = 1 for n > 5.
%e Triangle begins:
%e 1
%e 2
%e 4
%e 11
%e 33,1
%e 142,12,1,1
%e 822,169,39,10,2,1,1
%e 6966,3580,1241,378,120,36,16,5,2,1,1
%Y Cf. A000088 (number of simple graphs on n nodes).
%Y Cf. A005470 (number of planar simple graphs on n nodes).
%Y Cf. A000124 (central polygonal numbers).
%K nonn,tabf,more
%O 1,2
%A _Eric W. Weisstein_, Oct 25 2017
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