The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A359976 Number of edges formed inside a right triangle by the straight line segments mutually connecting all vertices and points on the two shorter edges whose positions on one edge equal the Farey series of order n while on the other they divide its length into n equal segments. 5
 3, 10, 55, 202, 902, 1868, 5886, 11676, 24322, 39440, 84155, 120151, 228121, 324856, 474396, 670552, 1104433, 1402237, 2185044, 2761367, 3654893, 4628608, 6706612, 8005739, 10770733 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The number of vertices on the edge with point positions equaling the Farey series of order n is A005728(n). No formula for a(n) is known. See A359974 and A359975 for images of the triangle. This graph is related to the 'Farey fan' given in the reference. REFERENCES McIlroy, M. D. "A Note on Discrete Representation of Lines". AT&T Technical Journal, 64 (1985), 481-490. LINKS Table of n, a(n) for n=1..25. FORMULA a(n) = A359974(n) + A359975(n) - 1 by Euler's formula. CROSSREFS Cf. A359974 (vertices), A359975 (regions), A359977 (k-gons), A005728, A359970, A359693, A358950, A358888. Sequence in context: A229311 A208480 A342966 * A034234 A284645 A081721 Adjacent sequences: A359973 A359974 A359975 * A359977 A359978 A359979 KEYWORD nonn,more AUTHOR Scott R. Shannon and N. J. A. Sloane, Jan 20 2023 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified June 13 08:31 EDT 2024. Contains 373383 sequences. (Running on oeis4.)