cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-4 of 4 results.

A335350 a(n) is the number of regions formed in a square by dividing each of its sides into n equal parts giving a total of 4*n nodes and drawing straight line segments from node k to node (k+n+1) mod 4*n, 0 <= k < 4*n.

Original entry on oeis.org

4, 25, 37, 81, 109, 169, 205, 289, 341, 441, 485, 625, 701, 825, 913, 1089, 1189, 1369, 1461, 1661, 1805, 2025, 2141, 2389, 2549, 2809, 2929, 3249, 3405, 3721, 3901, 4205, 4421, 4753, 4913, 5329, 5549, 5913, 6105, 6561, 6781, 7225, 7453, 7885, 8189, 8649
Offset: 1

Views

Author

Lars Blomberg, Jun 03 2020

Keywords

Comments

For n>1, a(n)-1 is divisible by 4.

Crossrefs

Cf. A335351 (edges), A335352 (vertices), A335353 (n-gons), A335354 (edges in central polygon), A255011, A335057, A335192.

A335352 a(n) is the number of vertices formed in a square by dividing each of its sides into n equal parts giving a total of 4*n nodes and drawing straight line segments from node k to node (k+n+1) mod 4*n, 0 <= k < 4*n.

Original entry on oeis.org

5, 24, 28, 80, 100, 168, 188, 288, 324, 440, 452, 624, 676, 808, 872, 1088, 1156, 1368, 1412, 1644, 1764, 2024, 2084, 2380, 2500, 2808, 2848, 3248, 3340, 3720, 3836, 4188, 4356, 4744, 4800, 5328, 5476, 5896, 5984, 6560, 6684, 7224, 7348, 7852, 8100, 8648
Offset: 1

Views

Author

Lars Blomberg, Jun 04 2020

Keywords

Comments

For n>1, a(n) is divisible by 4.
See A335350 for illustrations.

Crossrefs

Cf. A335350 (regions), A335351 (edges), A335353 (n-gons), A335354 (edges in central polygon), A255011, A335057, A335192.

A335353 Irregular table read by rows: Take a square and divide each of its sides into n equal parts giving a total of 4*n nodes, draw straight line segments from node k to node (k+n+1) mod 4*n, 0 <= k < 4*n. Then T(n,k) = number of k-sided polygons in that figure for k >= 3.

Original entry on oeis.org

4, 16, 8, 0, 0, 0, 1, 32, 5, 32, 40, 8, 0, 0, 1, 64, 28, 16, 0, 0, 0, 0, 0, 0, 1, 80, 56, 24, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 96, 84, 24, 0, 0, 0, 0, 0, 0, 1, 128, 100, 40, 20, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 144, 156, 32, 0, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1
Offset: 1

Views

Author

Lars Blomberg, Jun 04 2020

Keywords

Comments

See A335350 for illustrations.

Examples

			Table begins:
4;
16, 8, 0, 0, 0, 1;
32, 5;
32, 40, 8, 0, 0, 1;
64, 28, 16, 0, 0, 0, 0, 0, 0, 1;
80, 56, 24, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1;
96, 84, 24, 0, 0, 0, 0, 0, 0, 1;
128, 100, 40, 20, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1;
144, 156, 32, 0, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1;
168, 188, 64, 16, 0, 4, 0, 0, 0, 0, 0, 0, 0, 1;
200, 228, 40, 16, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1;
248, 252, 88, 24, 8, 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1;
		

Crossrefs

Cf. A335350 (regions), A335351 (edges), A335352 (vertices), A335354 (edges in central polygon), A255011, A335057, A335192.

A335354 a(n) is the number of edges in the central polygon formed in a square by dividing each of its sides into n equal parts giving a total of 4*n nodes and drawing straight line segments from node k to node (k+n+1) mod 4*n, 0 <= k < 4*n.

Original entry on oeis.org

0, 8, 4, 8, 12, 16, 12, 16, 20, 16, 20, 24, 28, 24, 28, 32, 28, 32, 36, 32, 36, 40, 44, 40, 44, 48, 44, 48, 52, 56, 52, 56, 60, 56, 60, 64, 68, 64, 68, 72, 68, 72, 76, 72, 76, 80, 84, 80, 84, 88, 84, 88, 92, 96, 92, 96, 100, 96, 100, 104, 100, 104, 108, 112
Offset: 1

Views

Author

Lars Blomberg, Jun 04 2020

Keywords

Comments

For n=1 there is no central polygon.
The number of edges of the central polygon tends to grow as n increases, whereas for n = 16..500 the polygon with next-to-most edges has 8 of them.
See A335350 for illustrations.

Crossrefs

Cf. A335350 (regions), A335351 (edges), A335352 (vertices), A335353 (n-gons), A255011, A335057, A335192.
Showing 1-4 of 4 results.