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.

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A265071 Coordination sequence for (3,3,4) tiling of hyperbolic plane.

Original entry on oeis.org

1, 3, 6, 10, 15, 22, 31, 44, 62, 87, 122, 171, 240, 336, 471, 660, 925, 1296, 1816, 2545, 3566, 4997, 7002, 9812, 13749, 19266, 26997, 37830, 53010, 74281, 104088, 145855, 204382, 286394, 401315, 562350, 788003, 1104204, 1547286, 2168163, 3038178, 4257303, 5965624, 8359440, 11713819, 16414204, 23000705, 32230160
Offset: 0

Views

Author

N. J. A. Sloane, Dec 29 2015

Keywords

Crossrefs

Programs

  • Magma
    I:=[1,3,6,10,15,22,31]; [n le 7 select I[n] else Self(n-2)+Self(n-3)+Self(n-4)- Self(n-6): n in [1..50]]; // Vincenzo Librandi, Dec 30 2015
    
  • Mathematica
    CoefficientList[Series[(x^3 + x^2 + x + 1) (x^2 + x + 1) (x + 1)/(x^6 - x^4 - x^3 - x^2 + 1), {x, 0, 60}], x] (* Vincenzo Librandi, Dec 30 2015 *)
  • PARI
    x='x+O('x^50); Vec((x^3+x^2+x+1)*(x^2+x+1)*(x+1)/(x^6-x^4-x^3-x^2+1)) \\ G. C. Greubel, Aug 07 2017

Formula

G.f.: (x^3+x^2+x+1)*(x^2+x+1)*(x+1)/(x^6-x^4-x^3-x^2+1).
a(n) = a(n-2)+a(n-3)+a(n-4)-a(n-6) for n>6. - Vincenzo Librandi, Dec 30 2015

A265072 Coordination sequence for (3,3,5) tiling of hyperbolic plane.

Original entry on oeis.org

1, 3, 6, 10, 16, 25, 38, 57, 86, 130, 196, 295, 444, 669, 1008, 1518, 2286, 3443, 5186, 7811, 11764, 17718, 26686, 40193, 60536, 91175, 137322, 206826, 311508, 469173, 706638, 1064293, 1602970, 2414290, 3636248, 5476683, 8248628, 12423553, 18711556, 28182142, 42446130, 63929631, 96286698, 145020831, 218421048
Offset: 0

Views

Author

N. J. A. Sloane, Dec 29 2015

Keywords

Crossrefs

Programs

  • Mathematica
    CoefficientList[Series[(x^2 + x + 1) (x^4 + x^3 + x^2 + x + 1)/(x^6 - x^5 - x^3 - x + 1), {x, 0, 60}], x] (* Vincenzo Librandi, Dec 30 2015 *)
    LinearRecurrence[{1,0,1,0,1,-1},{1,3,6,10,16,25,38},50] (* Harvey P. Dale, Oct 07 2022 *)
  • PARI
    x='x+O('x^50); Vec((x^2+x+1)*(x^4+x^3+x^2+x+1)/(x^6-x^5-x^3-x+1)) \\ G. C. Greubel, Aug 07 2017

Formula

G.f.: (x^2+x+1)*(x^4+x^3+x^2+x+1)/(x^6-x^5-x^3-x+1).

A265073 Coordination sequence for (3,3,6) tiling of hyperbolic plane.

Original entry on oeis.org

1, 3, 6, 10, 16, 26, 41, 64, 99, 154, 240, 374, 582, 905, 1408, 2191, 3410, 5306, 8256, 12846, 19989, 31104, 48399, 75310, 117184, 182342, 283730, 441493, 686976, 1068955, 1663326, 2588186, 4027296, 6266594, 9751009, 15172864, 23609435, 36736994, 57163872, 88948710, 138406878, 215365281, 335114880, 521448871
Offset: 0

Views

Author

N. J. A. Sloane, Dec 29 2015

Keywords

Crossrefs

Programs

  • Mathematica
    CoefficientList[Series[(x^3 + 1) (x^2 + x + 1) (x + 1)/(x^6 - x^5 - x^4 + x^3 - x^2 - x + 1), {x, 0, 60}], x] (* Vincenzo Librandi, Dec 30 2015 *)
  • PARI
    x='x+O('x^50); Vec((x^3+1)*(x^2+x+1)*(x+1)/(x^6-x^5-x^4+x^3-x^2-x+1)) \\ G. C. Greubel, Aug 07 2017

Formula

G.f.: (x^3+1)*(x^2+x+1)*(x+1)/(x^6-x^5-x^4+x^3-x^2-x+1).

A265074 Coordination sequence for (3,3,7) tiling of hyperbolic plane.

Original entry on oeis.org

1, 3, 6, 10, 16, 26, 42, 67, 106, 167, 264, 418, 662, 1048, 1658, 2623, 4150, 6567, 10392, 16444, 26020, 41172, 65148, 103087, 163120, 258113, 408424, 646268, 1022620, 1618140, 2560460, 4051537, 6410938, 10144329, 16051850, 25399600, 40190986, 63596094, 100631100, 159233337, 251962422, 398692029, 630869210
Offset: 0

Views

Author

N. J. A. Sloane, Dec 29 2015

Keywords

Crossrefs

Programs

  • Magma
    I:=[1,3,6,10,16,26,42,67,106]; [n le 9 select I[n] else Self(n-1)+Self(n-3)+Self(n-5)+Self(n-7)-Self(n-8): n in [1..50]]; // Vincenzo Librandi, Dec 30 2015
    
  • Mathematica
    CoefficientList[Series[(x^2 + x + 1) (x^6 + x^5 + x^4 + x^3 + x^2 + x + 1)/(x^8 - x^7 - x^5 - x^3 - x + 1), {x, 0, 60}], x] (* Vincenzo Librandi, Dec 30 2015 *)
  • PARI
    x='x+O('x^50); Vec((x^2+x+1)*(x^6+x^5+x^4+x^3+x^2+x+1)/(x^8-x^7-x^5-x^3-x+1)) \\ G. C. Greubel, Aug 07 2017

Formula

G.f.: (x^2+x+1)*(x^6+x^5+x^4+x^3+x^2+x+1)/(x^8-x^7-x^5-x^3-x+1).
a(n) = a(n-1)+a(n-3)+a(n-5)+a(n-7)-a(n-8) for n>8. - Vincenzo Librandi, Dec 30 2015

A265075 Coordination sequence for (3,4,4) tiling of hyperbolic plane.

Original entry on oeis.org

1, 3, 6, 11, 18, 29, 46, 73, 116, 183, 290, 459, 726, 1149, 1818, 2877, 4552, 7203, 11398, 18035, 28538, 45157, 71454, 113065, 178908, 283095, 447954, 708819, 1121598, 1774757, 2808282, 4443677, 7031440, 11126179, 17605478, 27857979, 44080994, 69751437, 110370990, 174645225, 276349380, 437280663, 691929826
Offset: 0

Views

Author

N. J. A. Sloane, Dec 29 2015

Keywords

Crossrefs

Programs

  • Mathematica
    CoefficientList[Series[(x^3 + x^2 + x + 1) (x^2 + x + 1) (x + 1)/(x^6 - x^4 - 2 x^3 - x^2 + 1), {x, 0, 60}], x] (* Vincenzo Librandi, Dec 30 2015 *)
  • PARI
    x='x+O('x^50); Vec((x^3+x^2+x+1)*(x^2+x+1)*(x+1)/(x^6-x^4-2*x^3-x^2+1)) \\ G. C. Greubel, Aug 07 2017

Formula

G.f.: (x^3+x^2+x+1)*(x^2+x+1)*(x+1)/(x^6-x^4-2*x^3-x^2+1).

A265076 Coordination sequence for (3,5,5) tiling of hyperbolic plane.

Original entry on oeis.org

1, 3, 6, 11, 20, 35, 60, 103, 178, 307, 528, 909, 1566, 2697, 4644, 7997, 13772, 23717, 40842, 70333, 121120, 208579, 359190, 618555, 1065204, 1834371, 3158940, 5439959, 9368066, 16132595, 27781680, 47842381, 82388590, 141880057, 244329348, 420755613, 724576428, 1247781333, 2148784026, 3700386173, 6372375104
Offset: 0

Views

Author

N. J. A. Sloane, Dec 29 2015

Keywords

Crossrefs

Programs

  • Mathematica
    CoefficientList[Series[(x^2 + x + 1) (x^4 + x^3 + x^2 + x + 1)/(x^6 - x^5 - 2 x^3 - x + 1), {x, 0, 60}], x] (* Vincenzo Librandi, Dec 30 2015 *)
  • PARI
    Vec((x^2+x+1)*(x^4+x^3+x^2+x+1)/(x^6-x^5-2*x^3-x+1) + O(x^50)) \\ Michel Marcus, Dec 30 2015

Formula

G.f.: (x^2+x+1)*(x^4+x^3+x^2+x+1)/(x^6-x^5-2*x^3-x+1).

A265077 Coordination sequence for (3,6,8) tiling of hyperbolic plane.

Original entry on oeis.org

1, 3, 6, 11, 20, 37, 66, 117, 208, 371, 662, 1179, 2100, 3741, 6666, 11877, 21160, 37699, 67166, 119667, 213204, 379853, 676762, 1205749, 2148216, 3827355, 6818982, 12148995, 21645180, 38563997, 68707298, 122411917, 218094408, 388566507, 692287030, 1233408755, 2197494812, 3915152565, 6975406506, 12427688349
Offset: 0

Views

Author

N. J. A. Sloane, Dec 29 2015

Keywords

Crossrefs

Programs

  • Magma
    I:=[1,3,6,11,20,37,66]; [n le 7 select I[n] else Self(n-1)+Self(n-2)+Self(n-4) + Self(n-5)-Self(n-6): n in [1..50]]; // Vincenzo Librandi, Dec 30 2015
  • Mathematica
    CoefficientList[Series[(x^5 + x^4 + x^3 + x^2 + x + 1) (x + 1)/(x^6 - x^5 - x^4 - x^2 - x + 1), {x, 0, 60}], x] (* Vincenzo Librandi, Dec 30 2015 *)
  • PARI
    Vec((x^5+x^4+x^3+x^2+x+1)*(x+1)/(x^6-x^5-x^4-x^2-x+1) + O(x^50)) \\ Michel Marcus, Dec 30 2015
    

Formula

G.f.: (x^5+x^4+x^3+x^2+x+1)*(x+1)/(x^6-x^5-x^4-x^2-x+1).
a(n) = a(n-1)+a(n-2)+a(n-4)+a(n-5)-a(n-6) for n>6. - Vincenzo Librandi, Dec 30 2015

A196456 T(n,k)=Number of nXk 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 3,0,2,4,1 for x=0,1,2,3,4.

Original entry on oeis.org

1, 3, 3, 4, 6, 4, 5, 14, 14, 5, 8, 30, 40, 30, 8, 12, 67, 131, 131, 67, 12, 17, 146, 383, 594, 383, 146, 17, 25, 320, 1232, 2930, 2930, 1232, 320, 25, 37, 706, 3966, 15274, 27320, 15274, 3966, 706, 37, 54, 1550, 12314, 76809, 249402, 249402, 76809, 12314, 1550, 54
Offset: 1

Views

Author

R. H. Hardin Oct 02 2011

Keywords

Comments

Every 0 is next to 0 3's, every 1 is next to 1 0's, every 2 is next to 2 2's, every 3 is next to 3 4's, every 4 is next to 4 1's
Table starts
..1....3......4.......5..........8..........12............17..............25
..3....6.....14......30.........67.........146...........320.............706
..4...14.....40.....131........383........1232..........3966...........12314
..5...30....131.....594.......2930.......15274.........76809..........380093
..8...67....383....2930......27320......249402.......2032584........15952022
.12..146...1232...15274.....249402.....3707781......46887621.......578160718
.17..320...3966...76809....2032584....46887621.....926499600.....17962317556
.25..706..12314..380093...15952022...578160718...17962317556....539621963877
.37.1550..38745.1900745..128543371..7394096617..351103877665..16067939829696
.54.3403.122989.9527317.1060801262.96338727461.6945098996988.486076221745274

Examples

			Some solutions for n=6 k=4
..0..0..1..1....0..1..1..0....1..0..0..0....0..0..0..1....0..0..0..1
..1..1..1..0....2..2..1..0....1..0..0..0....1..1..1..1....0..0..2..2
..1..1..4..1....2..2..1..0....2..2..0..0....2..2..2..0....0..0..2..2
..0..0..1..1....0..1..1..0....2..2..0..0....2..0..2..0....2..2..1..0
..0..2..2..0....0..1..1..1....0..0..0..0....2..2..2..0....2..2..1..1
..1..2..2..1....1..1..0..1....1..1..1..1....0..0..0..0....0..0..0..1
		

Crossrefs

Column 1 is A179070(n+2)

A196146 T(n,k)=Number of nXk 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 3,0,4,1,2 for x=0,1,2,3,4.

Original entry on oeis.org

1, 3, 3, 4, 5, 4, 5, 8, 8, 5, 8, 17, 7, 17, 8, 12, 34, 26, 26, 34, 12, 17, 62, 49, 83, 49, 62, 17, 25, 123, 85, 168, 168, 85, 123, 25, 37, 243, 178, 346, 481, 346, 178, 243, 37, 54, 471, 348, 865, 1031, 1031, 865, 348, 471, 54, 79, 924, 683, 2055, 2781, 2599, 2781, 2055
Offset: 1

Views

Author

R. H. Hardin Sep 28 2011

Keywords

Comments

Every 0 is next to 0 3's, every 1 is next to 1 0's, every 2 is next to 2 4's, every 3 is next to 3 1's, every 4 is next to 4 2's
Table starts
..1...3....4.....5.....8.....12.....17......25.......37.......54........79
..3...5....8....17....34.....62....123.....243......471......924......1817
..4...8....7....26....49.....85....178.....348......683.....1349......2688
..5..17...26....83...168....346....865....2055.....4745....10866.....24967
..8..34...49...168...481...1031...2781....7666....19581....50767....133067
.12..62...85...346..1031...2599...7486...22292....61689...177057....510032
.17.123..178...865..2781...7486..24615...85533...266059...866323...2817802
.25.243..348..2055..7666..22292..85533..330889..1154587..4208560..15450981
.37.471..683..4745.19581..61689.266059.1154587..4431097.17980473..73718035
.54.924.1349.10866.50767.177057.866323.4208560.17980473.82611569.381145071

Examples

			Some solutions for n=6 k=4
.0.1.1.0...0.1.1.0...1.1.0.1...0.1.1.0...1.0.1.1
.1.3.1.0...0.1.1.0...0.1.1.1...0.1.1.0...1.1.1.0
.1.3.1.0...1.3.1.0...0.1.1.0...0.1.3.1...0.1.3.1
.0.1.1.0...1.3.1.0...0.1.1.0...0.1.3.1...0.1.3.1
.0.1.1.0...0.1.1.0...1.1.1.1...1.1.1.0...0.1.1.0
.1.3.1.0...1.3.1.0...1.0.0.1...1.0.1.1...1.3.1.0
		

Crossrefs

Column 1 is A179070(n+2)

A196210 T(n,k)=Number of nXk 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 2,0,3,4,1 for x=0,1,2,3,4.

Original entry on oeis.org

1, 3, 3, 4, 5, 4, 5, 8, 8, 5, 8, 11, 7, 11, 8, 12, 18, 14, 14, 18, 12, 17, 28, 17, 35, 17, 28, 17, 25, 43, 27, 70, 70, 27, 43, 25, 37, 67, 42, 136, 135, 136, 42, 67, 37, 54, 105, 58, 305, 301, 301, 305, 58, 105, 54, 79, 164, 94, 611, 751, 899, 751, 611, 94, 164, 79, 116, 257, 137
Offset: 1

Views

Author

R. H. Hardin Sep 29 2011

Keywords

Comments

Every 0 is next to 0 2's, every 1 is next to 1 0's, every 2 is next to 2 3's, every 3 is next to 3 4's, every 4 is next to 4 1's
Table starts
..1...3...4....5.....8....12.....17......25.......37........54........79
..3...5...8...11....18....28.....43......67......105.......164.......257
..4...8...7...14....17....27.....42......58.......94.......137.......208
..5..11..14...35....70...136....305.....611.....1321......2832......6041
..8..18..17...70...135...301....751....1774.....4243.....10211.....24823
.12..28..27..136...301...899...2922....7680....24326.....71539....213378
.17..43..42..305...751..2922..10986...35529...128823....472599...1687338
.25..67..58..611..1774..7680..35529..136967...627285...2695504..11805281
.37.105..94.1321..4243.24326.128823..627285..3421139..17683925..93767603
.54.164.137.2832.10211.71539.472599.2695504.17683925.111262773.726204291

Examples

			Some solutions for n=6 k=4
..0..0..1..1....1..0..0..1....0..1..1..0....1..0..1..1....0..1..1..0
..1..1..1..0....1..0..0..1....0..1..1..0....1..1..1..0....1..1..1..0
..1..4..1..0....1..0..0..1....1..1..4..1....0..1..1..0....1..0..1..1
..0..1..1..0....1..0..0..1....1..0..1..1....0..1..1..0....1..0..1..1
..1..1..1..1....1..0..0..1....1..1..1..0....1..1..1..1....1..1..1..0
..1..0..0..1....1..0..0..1....0..1..1..0....1..0..0..1....0..1..1..0
		

Crossrefs

Column 1 is A179070(n+2)
Previous Showing 21-30 of 43 results. Next