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A327201 Irregular triangle read by rows with trailing zeros removed where T(n,k) is the number of unlabeled simple graphs covering n vertices with non-spanning edge-connectivity k.

%I A327201 #4 Sep 03 2019 09:57:44
%S A327201 1,0,1,0,0,1,1,1,1,2,2,1,2,3,7,5,4,1,1
%N A327201 Irregular triangle read by rows with trailing zeros removed where T(n,k) is the number of unlabeled simple graphs covering n vertices with non-spanning edge-connectivity k.
%C A327201 The non-spanning edge-connectivity of a graph is the minimum number of edges that must be removed to obtain a disconnected or empty graph, ignoring isolated vertices.
%H A327201 Gus Wiseman, <a href="/A327201/a327201.png">Unlabeled graphs covering 5 vertices, organized by non-spanning edge-connectivity.</a>
%e A327201 Triangle begins:
%e A327201   1
%e A327201   {}
%e A327201   0 1
%e A327201   0 0 1 1
%e A327201   1 1 2 2 1
%e A327201   2 3 7 5 4 1 1
%Y A327201 Row sums are A002494.
%Y A327201 Column k = 0 is A327075.
%Y A327201 The labeled version is A327149.
%Y A327201 Spanning edge-connectivity is A263296.
%Y A327201 The non-covering version is A327236 (partial sums).
%Y A327201 Cf. A000088, A322338, A322396, A326787, A327076, A327077, A327079, A327126, A327129, A327148, A327235.
%K A327201 nonn,tabf,more
%O A327201 0,10
%A A327201 _Gus Wiseman_, Sep 03 2019