A358303 Number of 4-sided regions in the Farey Diagram Farey(n,n), divided by 8.

1, 13, 57, 231, 532, 1497, 2935, 6031, 10273, 19680, 29441, 51261, 74473, 112721, 159299, 242763, 317155, 462930, 598755, 808780, 1035705, 1414983, 1728181, 2282397, 2805375, 3558815, 4306631, 5516710, 6435770, 8126946, 9611708, 11649506, 13656195, 16574211

Offset

2,2

Comments

This is the second column in A358885, divided by 8.

It would be nice to have a formula.

Links

Table of n, a(n) for n=2..35.

Crossrefs

The Farey Diagrams Farey(m,n) are studied in A358298-A358307 and A358882-A358885, the Completed Farey Diagrams of order (m,n) in A358886-A358889.

Sequence in context: A368813 A222161 A218593 * A212405 A147384 A147011

Adjacent sequences: A358300 A358301 A358302 * A358304 A358305 A358306

Keyword

nonn

Author

Scott R. Shannon and N. J. A. Sloane, Dec 06 2022

Extensions

Offset corrected and a(20)-a(35) from Martin Fuller, Jan 14 2026

Status

approved