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A357856
Number of trails between two fixed distinct vertices in the complete undirected graph on n labeled vertices.
9
0, 1, 2, 15, 514, 106085, 317848626, 4238195548627, 2617666555119413330
OFFSET
1,3
COMMENTS
Trails are directed and pass through each (undirected) edge at most once in either of the two directions.
FORMULA
a(n) = Sum_{k = 0..n(n-1)/2} A357886(n,k).
KEYWORD
nonn,more,walk
AUTHOR
Max Alekseyev, Oct 16 2022
EXTENSIONS
a(9) from Bert Dobbelaere, Oct 17 2022
STATUS
approved