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A359690
Number of vertices in a regular drawing of a complete bipartite graph where the vertex positions on each part equal the Farey series of order n.
10
5, 13, 69, 289, 1971, 3997, 20371, 45751, 120957, 205299, 629847, 897801, 2334409, 3461459, 5517131, 8468061
OFFSET
1,1
COMMENTS
The number of vertices along each edge is A005728(n). No formula for a(n) is known.
LINKS
Scott R. Shannon, Image for n = 1.
Scott R. Shannon, Image for n = 2.
Scott R. Shannon, Image for n = 3.
Scott R. Shannon, Image for n = 4.
Scott R. Shannon, Image for n = 5.
Scott R. Shannon, Image for n = 6.
Scott R. Shannon, Image for n = 7.
Eric Weisstein's World of Mathematics, Complete Bipartite Graph.
Wikipedia, Farey sequence.
FORMULA
a(n) = A359693(n) - A359692(n) + 1 by Euler's formula.
CROSSREFS
Cf. A359691 (crossings), A359692 (regions), A359693 (edges), A359694 (k-gons), A005728, A331755, A359654, A358887, A358883, A006842, A006843.
Sequence in context: A156101 A372799 A093118 * A087506 A068487 A075063
KEYWORD
nonn,more
AUTHOR
STATUS
approved