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%I #11 Dec 19 2017 18:40:09
%S 1,0,3,0,60,0,5457,2391,0,258474,3200871,37,1,0,1041762,2583730089,
%T 364670,154,0
%N Number of 5-regular (quintic) connected graphs on 2*n nodes with diameter k written as irregular triangle T(n,k).
%C The results were found by applying the Floyd-Warshall algorithm to the output of Markus Meringer's GenReg program.
%H M. Meringer, <a href="https://sourceforge.net/projects/genreg/">GenReg</a>, Generation of regular graphs.
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Distance_(graph_theory)">Distance (graph theory).</a>
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Floyd%E2%80%93Warshall_algorithm">Floyd-Warshall algorithm.</a>
%e Triangle begins:
%e Diameter
%e n/ 1 2 3 4 5
%e 6: 0 1
%e 8: 0 3
%e 10: 0 60
%e 12: 0 5457 2391
%e 14: 0 258474 3200871 37 1
%e 16: 0 1041762 2583730089 364670 154
%e .
%e The adjacency matrix of the unique 5-regular graph on 14 nodes with diameter 5 is provided as example in A296526.
%Y Cf. A006821 (row sums), A068934, A204329, A296525 (number of terms in each row), A296526, A296620.
%K nonn,tabf,more
%O 3,3
%A _Hugo Pfoertner_, Dec 19 2017
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