A369176 Number of vertices in a graph of n adjacent rectangles in a row with all possible diagonals drawn, as in A306302, but without the rectangles' edges which are perpendicular to the row.

5, 13, 31, 67, 139, 247, 429, 691, 1067, 1543, 2217, 3047, 4169, 5495, 7117, 9031, 11449, 14179, 17547, 21379, 25835, 30755, 36613, 43091, 50605, 58775, 68035, 78171, 89831, 102335, 116593, 132079, 149181, 167391, 187497, 208983, 232977, 258351, 285957, 315323, 347777, 381867, 419371

Offset: 1

Author

Scott R. Shannon, Jan 15 2024

Keywords

• nonn

Links

• Scott R. Shannon, Image for n = 1.
• Scott R. Shannon, Image for n = 2.
• Scott R. Shannon, Image for n = 8.

Crossrefs

Cf. A369175 (regions), A369177 (edges), A369178 (k-gons), A306302, A331755, A368756.

Formula

a(n) = A369177(n) - A369175(n) + 1 by Euler's formula.