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A301731 revision #2

A301731
Triangle read by rows: T(n,m) = one-half of number of embeddings of the n-wheel with k = n+1-2m regions (n >= 1, 0 <= m <= floor(n/2)).
1
1, 1, 1, 1, 7, 1, 29, 18, 1, 95, 288, 1, 275, 2484, 1080, 1, 742, 15589, 29748
OFFSET
1,5
REFERENCES
Yichao Chen et al., On the genus distribution of wheels ..., Discrete Math., 341 (2018), 934-935.
FORMULA
Theorem 3.4 of Chen et al. (2018) gives a formula.
EXAMPLE
Triangle begins:
1,
1,1,
1,7,
1,29,18,
1,95,288,
1,275,2484,1080,
1,742,15589,29748,
...
CROSSREFS
Sequence in context: A146996 A286895 A083994 * * A228498 A084181
KEYWORD
nonn,tabf,more,new
AUTHOR
N. J. A. Sloane, Apr 03 2018
STATUS
editing