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A308568 Number of simple graphs on n vertices with bandwidth equal to diameter-based lower bound. 0
1, 2, 6, 14, 84, 286, 7266, 63191 (list; graph; refs; listen; history; text; internal format)
OFFSET
2,2
COMMENTS
Number of graphs for which the inequality bw(G) >= ceiling((n-1)/diameter(G)) holds with equality.
Equality holds for all nontrivial simple connected graphs on <= 4 nodes, so a(n) = A001349(n) for n = 2, 3, 4.
LINKS
Eric Weisstein's World of Mathematics, Graph Bandwidth
Eric Weisstein's World of Mathematics, Graph Diameter
EXAMPLE
14 of the 21 graphs on 5 nodes satisfy the inequality with equality, the exceptions being K_2,3, K_1,1,3, K_1,1,1,2, W_5, the house X graph, the (4,1)-lollipop graph, and one other.
CROSSREFS
Sequence in context: A055691 A072171 A371008 * A296054 A333121 A131518
KEYWORD
nonn,more
AUTHOR
Eric W. Weisstein, Jun 11 2019
STATUS
approved

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Last modified March 28 10:55 EDT 2024. Contains 371241 sequences. (Running on oeis4.)