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A263296
Triangle read by rows: T(n,k) is the number of graphs with n vertices with edge connectivity k.
23
1, 1, 1, 2, 1, 1, 5, 3, 2, 1, 13, 10, 8, 2, 1, 44, 52, 41, 15, 3, 1, 191, 351, 352, 121, 25, 3, 1, 1229, 3714, 4820, 2159, 378, 41, 4, 1, 13588, 63638, 113256, 68715, 14306, 1095, 65, 4, 1, 288597, 1912203, 4602039, 3952378, 1141575, 104829, 3441, 100, 5, 1
OFFSET
1,4
COMMENTS
This is spanning edge-connectivity. The spanning edge-connectivity of a graph is the minimum number of edges that must be removed (without removing incident vertices) to obtain a graph that is disconnected or covers fewer vertices. The non-spanning edge-connectivity of a graph (A327236) is the minimum number of edges that must be removed to obtain a graph whose edge-set is disconnected or empty. Compare to vertex-connectivity (A259862). - Gus Wiseman, Sep 03 2019
EXAMPLE
Triangle begins:
1;
1, 1;
2, 1, 1;
5, 3, 2, 1;
13, 10, 8, 2, 1;
44, 52, 41, 15, 3, 1;
191, 351, 352, 121, 25, 3, 1;
1229, 3714, 4820, 2159, 378, 41, 4, 1;
...
CROSSREFS
Row sums give A000088, n >= 1.
Number of graphs with edge connectivity at least k for k=1..10 are A001349, A007146, A324226, A324227, A324228, A324229, A324230, A324231, A324232, A324233.
The labeled version is A327069.
Sequence in context: A294758 A125800 A264698 * A259862 A182930 A372725
KEYWORD
nonn,tabl
AUTHOR
Christian Stump, Oct 13 2015
EXTENSIONS
a(22)-a(55) added by Andrew Howroyd, Aug 11 2019
STATUS
approved