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Triangle read by rows: T(n,k) is the number of connected graphs with n nodes and degeneracy k, 0 <= k < n.
2

%I #18 Mar 07 2022 07:55:46

%S 1,0,1,0,1,1,0,2,3,1,0,3,13,4,1,0,6,62,37,6,1,0,11,364,393,77,7,1,0,

%T 23,2799,6485,1665,135,9,1,0,47,27811,158766,68957,5268,220,10,1,0,

%U 106,349306,5718805,5091421,541593,14997,330,12,1

%N Triangle read by rows: T(n,k) is the number of connected graphs with n nodes and degeneracy k, 0 <= k < n.

%H Pontus von Brömssen, <a href="/A352067/b352067.txt">Rows n = 1..11, flattened</a>

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Degeneracy_(graph_theory)">Degeneracy</a>

%e Triangle begins:

%e n\k| 0 1 2 3 4 5 6 7 8 9

%e ---+----------------------------------------------------

%e 1 | 1

%e 2 | 0 1

%e 3 | 0 1 1

%e 4 | 0 2 3 1

%e 5 | 0 3 13 4 1

%e 6 | 0 6 62 37 6 1

%e 7 | 0 11 364 393 77 7 1

%e 8 | 0 23 2799 6485 1665 135 9 1

%e 9 | 0 47 27811 158766 68957 5268 220 10 1

%e 10 | 0 106 349306 5718805 5091421 541593 14997 330 12 1

%Y Row sums: A001349, column k=1: A000055.

%K nonn,tabl

%O 1,8

%A _Pontus von Brömssen_, Mar 05 2022