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 1-6 of 6 results.

A333544 Irregular triangle read by rows, formed from the triangle A333543 by dividing the terms in row n by n!.

Original entry on oeis.org

1, 2, 12, 4, 6784, 4024, 4936, 2704, 1912, 936, 824, 496, 360, 352, 256, 72, 48, 16, 16, 16
Offset: 1

Views

Author

N. J. A. Sloane, Apr 21 2020

Keywords

Comments

Rows 1 through 4 computed by Veit Elser, later confirmed by Tom Karzes.
Row sums are A333540.
See A333543 for further information.

Examples

			Triangle begins:
1,
2,
12, 4,
6784, 4024, 4936, 2704, 1912, 936, 824, 496, 360, 352, 256, 72, 48, 16, 16, 16
...
		

References

Crossrefs

A338622 Irregular table read by rows: The number of k-faced polyhedra, where k>=4, formed when the five Platonic solids, in the order tetrahedron, octahedron, cube, icosahedron, dodecahedron, are internally cut by all the planes defined by any three of their vertices.

Original entry on oeis.org

1, 8, 72, 24, 2160, 360, 205320, 208680, 94800, 34200, 7920, 1560, 120
Offset: 1

Views

Author

Scott R. Shannon, Nov 04 2020

Keywords

Comments

See A338571 for further details and images of this sequence.
The author thanks Zach J. Shannon for producing the images for this sequence.

Examples

			The cube is cut with 14 internal planes defined by all 3-vertex combinations of its 8 vertices. This leads to the creation of 72 4-faced polyhedra and 24 5-faced polyhedra, 96 pieces in all. See A338571 and A333539.
The table is:
1;
8;
72, 24;
2160, 360;
205320, 208680, 94800, 34200, 7920, 1560, 120;
		

Crossrefs

Cf. A338571 (total number of polyhedra), A333539 (n-dimensional cube), A053016, A063722, A063723, A098427, A333543.

Formula

Sum of row n = A338571(n).

A333539 Number of pieces formed when an n-dimensional cube is cut by all the hyperplanes defined by any n of the 2^n vertices.

Original entry on oeis.org

1, 4, 96, 570048
Offset: 1

Views

Author

N. J. A. Sloane, Apr 14 2020, in response to a question raised by Scott R. Shannon

Keywords

Examples

			The two diagonals of a square cut it into four pieces, so a(2) = 4.
For the cube the answer is 96 regions.  There are 14 cuts through the cube: six cut the cube in half along a face diagonal, and eight cut off a corner with a triangle through the three adjacent corners. The cuts through the center alone divide the cube into 24 regions, and then the corner cuts further divide each of these into four regions. - _Tomas Rokicki_, Apr 11 2020
		

References

Crossrefs

For the number of hyperplanes see A007847.
Cf. A333540, A338571 (number of pieces for the 3D Platonic solids).
For a more detailed count, see A333543 and A333544.

A338801 Irregular table read by rows: The number of k-faced polyhedra, where k>=4, created when an n-prism, formed from two n-sided regular polygons joined by n adjacent rectangles, is internally cut by all the planes defined by any three of its vertices.

Original entry on oeis.org

17, 0, 1, 72, 24, 575, 450, 232, 60, 15, 0, 3, 1728, 1668, 948, 144, 24, 12, 8799, 10080, 6321, 3052, 898, 490, 161, 14, 35, 14, 7, 22688, 24080, 12784, 4160, 1248, 272, 80, 32, 78327, 101142, 70254, 39708, 19584, 6894, 2369, 1062, 351, 54, 27, 18, 27, 36, 11, 165500, 203220, 134860, 62520, 21240, 5720, 1080, 300, 100, 20
Offset: 3

Views

Author

Scott R. Shannon, Nov 10 2020

Keywords

Comments

See A338783 for further details and images for this sequence.
The author thanks Zach J. Shannon for assistance in producing the images for this sequence.

Examples

			The triangular 3-prism is cut with 6 internal planes defined by all 3-vertex combinations of its 6 vertices. This leads to the creation of seventeen 4-faced polyhedra and one 6-faced polyhedra, eighteen pieces in all. The single 6-faced polyhedra lies at the very center of the original 3-prism.
The 9-prism is cut with 207 internal planes leading to the creation of 319864 pieces. It is noteworthy in creating all k-faced polyhedra from k=4 to k=18.
The table begins:
17,0,1;
72,24;
575,450,232,60,15,0,3;
1728,1668,948,144,24,12;
8799,10080,6321,3052,898,490,161,14,35,14,7;
22688,24080,12784,4160,1248,272,80,32;
78327,101142,70254,39708,19584,6894,2369,1062,351,54,27,18,27,36,11;
165500,203220,134860,62520,21240,5720,1080,300,100,20;
		

Crossrefs

Cf. A338783 (number of polyhedra), A338808 (antiprism), A338622 (Platonic solids), A333543 (n-dimensional cube).

Formula

Sum of row n = A338783(n).

A338808 Irregular table read by rows: The number of k-faced polyhedra, where k>=4, created when an n-antiprism, formed from two n-sided regular polygons joined by 2n adjacent alternating triangles, is internally cut by all the planes defined by any three of its vertices.

Original entry on oeis.org

8, 128, 56, 8, 0, 3, 450, 270, 82, 20, 10, 0, 2, 2592, 2376, 972, 204, 168, 48, 0, 0, 5, 7266, 7574, 4550, 2254, 660, 336, 98, 14, 14, 0, 2, 0, 0, 0, 0, 0, 0, 2, 27216, 31088, 15632, 5360, 1904, 432, 128, 0, 0, 0, 0, 0, 9, 68778, 84240, 61272, 33138, 15714, 5400, 1946, 720, 270, 126, 72, 18, 0, 0, 4, 0, 0, 0, 0, 0, 0, 0, 0, 4
Offset: 3

Views

Author

Scott R. Shannon, Nov 10 2020

Keywords

Comments

See A338806 for further details and images for this sequence.
The author thanks Zach J. Shannon for assistance in producing the images for this sequence.

Examples

			The 4-antiprism is cut with 16 internal planes defined by all 3-vertex combinations of its 8 vertices. This leads to the creation of 128 4-faced polyhedra, 56 5-faced polyhedra, 8 6-faced polyhedra, and 3 8-faced polyhedra, 195 pieces in all. Note the number of 8-faced polyhedra is not a multiple of 4 - they lie directly along the z-axis so need not be a multiple of the number of edges forming the regular n-gons.
The table begins:
8;
128,56,8,0,3;
450,270,82,20,10,0,2;
2592,2376,972,204,168,48,0,0,5;
7266,7574,4550,2254,660,336,98,14,14,0,2,0,0,0,0,0,0,2;
27216,31088,15632,5360,1904,432,128,0,0,0,0,0,9;
68778,84240,61272,33138,15714,5400,1946,720,270,126,72,18,0,0,4,0,0,0,0,0,0,0,0,4;
194580,235880,153620,68580,25240,7460,2560,660,200,0,0,0,0,0,0,0,13;
		

Crossrefs

Cf. A338806 (number of polyhedra), A338801 (regular prism), A338622 (Platonic solids), A333543 (n-dimensional cube).

Formula

Sum of row n = A338806(n).

A338825 Irregular table read by rows: The number of k-faced polyhedra, where k >= 4, created when an n-bipyramid, formed from two n-gonal pyraminds joined at the base, is internally cut by all the planes defined by any three of its vertices.

Original entry on oeis.org

12, 8, 120, 84, 24, 448, 280, 28, 368, 256, 48, 32, 1332, 1440, 540, 72, 1160, 1380, 500, 220, 40, 40, 2992, 5280, 2816, 748, 44, 3288, 4272, 1608, 672, 192, 7176, 14040, 8684, 3120, 624, 156, 8120, 12460, 7084, 2968, 1064, 532, 84, 14820, 34020, 22620, 7560, 2580, 720, 120
Offset: 3

Views

Author

Scott R. Shannon, Nov 11 2020

Keywords

Comments

See A338809 for further details and images for this sequence.
The author thanks Zach J. Shannon for assistance in producing the images for this sequence.

Examples

			The 4-bipyramid (an octahedron) is cut with 3 internal planes defined by all 3-vertex combinations of its 6 vertices. This leads to the creation of 8 4-faced polyhedra. See A338622.
The 7-bipyramid is cut with 36 internal planes defined by all 3-vertex combinations of its 9 vertices. This leads to the creation of 448 4-faced polyhedra, 280 5-faced polyhedra, and 28 6-faced polyhedra, 756 polyhedra in all.
The table begins:
     12;
      8;
    120;
     84,     24;
    448,    280,     28;
    368,    256,     48,    32;
   1332,   1440,    540,    72;
   1160,   1380,    500,   220,    40,   40;
   2992,   5280,   2816,   748,    44;
   3288,   4272,   1608,   672,   192;
   7176,  14040,   8684,  3120,   624,  156;
   8120,  12460,   7084,  2968,  1064,  532,   84;
  14820,  34020,  22620,  7560,  2580,  720,  120;
  18528,  28480,  18560,  9024,  2592, 1024,  384,  64;
  32028,  66708,  51136, 22372,  7956, 1836,  136;
  35280,  53028,  37080, 14364,  4104,  360,  180, 144;
  57380, 131480, 104576, 50616, 17328, 4256,   76;
  69160, 123040,  86240, 46080, 17600, 5920, 1920, 320, 320;
		

Crossrefs

Cf. A338809 (number of polyhedra), A338622 (Platonic solids), A333543 (n-dimensional cube).

Formula

Sum of row n = A338809(n).
Showing 1-6 of 6 results.