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%I #14 Nov 22 2020 12:16:46
%S 3,1,6,2,3,1,10,8,9,4,1,15,20,25,4,10,5,1,21,40,60,24,25,15,6,1,28,70,
%T 126,84,70,6,35,21,7,1,36,112,238,224,196,48,77,56,28,8,1,45,168,414,
%U 504,504,216,189,8,126,84,36,9,1,55,240,675,1008,1170,720,525,80,261,210,120,45,10,1
%N Irregular triangle read by rows: row n gives the multiplicities of the eigenvalues of the tree graph of the hammock graph P(n+1,2), in order from smallest to largest eigenvalue.
%H James R. Mahoney, <a href="https://doi.org/10.15760/etd.2939">Tree Graphs and Orthogonal Spanning Tree Decompositions</a>, PhD Dissertation, Portland State Univ., 2016.
%e Triangle begins:
%e 3,1,
%e 6,2,3,1,
%e 10,8,9,4,1,
%e 15,20,25,4,10,5,1,
%e 21,40,60,24,25,15,6,1,
%e 28,70,126,84,70,6,35,21,7,1,
%e 36,112,238,224,196,48,77,56,28,8,1,
%e 45,168,414,504,504,216,189,8,126,84,36,9,1,
%e 55,240,675,1008,1170,720,525,80,261,210,120,45,10,1,
%e ...
%K nonn,tabf
%O 2,1
%A _N. J. A. Sloane_, Jul 07 2017
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