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.

A367277 Place n equally spaced points on each side of a square, and join each of these points by a chord to the 3*n new points on the other three sides: sequence gives number of interior vertices in the resulting planar graph.

Original entry on oeis.org

0, 1, 57, 329, 1317, 2861, 7417, 12801, 23329, 36549, 64625, 80085, 138261, 176829, 233705, 311949, 455205, 513205, 741889, 819509, 1046161, 1310673, 1692869, 1772001, 2315189, 2713893, 3165017, 3552641, 4538729, 4602865, 6015437, 6432553, 7421213, 8550349, 9439481, 10063849, 12635621
Offset: 0

Views

Author

Scott R. Shannon, Nov 11 2023

Keywords

Comments

See A367276 for further information.

Crossrefs

Cf. A367276 (interior), A367278 (regions), A367279 (edges).

Formula

a(n) = A367279(n) - A367278(n) - 4*n - 3 (Euler).

A367278 Place n equally spaced points on each side of a square, and join each of these points by a chord to the 3*n new points on the other three sides: sequence gives number of regions in the resulting planar graph.

Original entry on oeis.org

1, 8, 88, 444, 1544, 3584, 8356, 14996, 26572, 42144, 69988, 93264, 148364, 196120, 261536, 347544, 483056, 572832, 783252, 907472, 1141668, 1413512, 1775972, 1958684, 2466452, 2897004, 3384128, 3852068, 4733632, 5042324, 6263264, 6869784, 7878988, 9014840, 10035784, 10909592, 13109608
Offset: 0

Views

Author

Scott R. Shannon, Nov 11 2023

Keywords

Comments

See A367276 for further information.

Crossrefs

Cf. A367276 (vertices), A367277 (interior vertices), A367279 (edges).

Formula

a(n) = A367279(n) - A367276(n) + 1 (Euler).

A367279 Place n equally spaced points on each side of a square, and join each of these points by a chord to the 3*n new points on the other three sides: sequence gives number of edges in the resulting planar graph.

Original entry on oeis.org

4, 16, 156, 788, 2880, 6468, 15800, 27828, 49936, 78732, 134656, 173396, 286676, 373004, 495300, 659556, 938328, 1086108, 1525216, 1727060, 2187912, 2724272, 3468932, 3730780, 4781740, 5611000, 6549252, 7404820, 9272476, 9645308, 12278824, 13302464, 15300332, 17565324, 19475404, 20973584
Offset: 0

Views

Author

Scott R. Shannon, Nov 11 2023

Keywords

Comments

See A367276 for further information. See A367276 and A367278 for images of the square.

Crossrefs

Cf. A367276 (vertices), A367277 (interior vertices), A367278 (regions).

Formula

a(n) = A367276(n) + A367278(n) - 1 (Euler).

A367302 Table read by antidiagonals: Place k equally spaced points on each side of a regular n-gon and join every pair of these n*k points by a chord; T(n,k) (n >= 3, k >= 0) gives the number of vertices in the resulting planar graph.

Original entry on oeis.org

3, 6, 4, 22, 9, 5, 108, 69, 15, 6, 300, 345, 215, 25, 7, 919, 1337, 1285, 397, 49, 8, 1626, 2885, 4435, 2461, 1008, 65, 9, 3558, 7445, 11310, 7873, 5817, 1601, 144, 10, 5824, 12833, 24490, 21271, 19677, 9225, 3069, 181, 11, 9843, 23365, 46610, 46183, 49973, 33201, 17316, 4401, 352, 12
Offset: 3

Views

Author

Scott R. Shannon, Nov 13 2023

Keywords

Comments

See A366483 and A367276 for other images of the n-gons.

Examples

			The table begins:
3, 6, 22, 108, 300, 919, 1626, 3558, 5824, 9843, 14352, 23845, 30951, 47196, ...
4, 9, 69, 345, 1337, 2885, 7445, 12833, 23365, 36589, 64669, 80133, 138313, ...
5, 15, 215, 1285, 4435, 11310, 24490, 46610, 81005, 131560, 202610, 298690, ...
6, 25, 397, 2461, 7873, 21271, 46183, 87475, 150445, 249985, 388885, 569839, ...
7, 49, 1008, 5817, 19677, 49973, 106169, 200564, 346682, 560672, 861329, ...
8, 65, 1601, 9225, 33201, 83361, 182705, 341433, 597169, 961761, 1490689, ...
9, 144, 3069, 17316, 57555, 145062, 306684, 576783, 994230, 1605357, 2462112, ...
10, 181, 4401, 25201, 87301, 218211, 469401, 877291, 1522231, 2452231, 3781541, ...
11, 352, 7326, 40568, 133793, 335192, 706387, 1324851, 2279794, 3676431, ...
12, 325, 7897, 53125, 182713, 456253, 990229, 1849549, 3207325, 5171497, ...
13, 741, 14963, 81757, 267995, 668811, 1406366, 2632708, 4524910, ...
14, 785, 19489, 107157, 360389, 893117, 1896665, 3536387, 6103889, ...
15, 1395, 27420, 148335, 484005, 1204395, 2528445, 4726770, 8116650, ...
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Crossrefs

Cf. A367303 (internal vertices), A367304 (regions), A367305 (edges), A366483 (first row), A367276 (second row).

Formula

a(n,k) = A367305(n,k) - A367304(n,k) + 1 (Euler).
Showing 1-4 of 4 results.