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.

A264237 Sum of values of vertices at level n of the hyperbolic Pascal pyramid.

Original entry on oeis.org

1, 3, 9, 33, 165, 1137, 9837, 95193, 962541, 9884889, 102049197, 1055383929, 10921055661, 113032307769, 1169952636525, 12109971475065, 125349031354029, 1297477519769145, 13430093334225645, 139013932289379321, 1438923355509080877, 14894194022848480185
Offset: 0

Views

Author

Michel Marcus, Nov 09 2015

Keywords

Crossrefs

Programs

  • Mathematica
    CoefficientList[Series[-(20*x^5 - 8*x^4 + 58*x^3 - 54*x^2 + 15*x - 1)/((x - 1)*(2*x^2 - 4*x + 1)*(6*x^3 - 28*x^2 + 13*x - 1)), {x, 0, 20}], x] (* Wesley Ivan Hurt, Sep 17 2017 *)
  • PARI
    Vec(-(20*x^5-8*x^4+58*x^3-54*x^2+15*x-1)/((x-1)*(2*x^2-4*x+1)*(6*x^3-28*x^2+13*x-1)) + O(x^30)) \\ Colin Barker, Nov 09 2015

Formula

a(n) = 18*a(n-1) - 99*a(n-2) + 226*a(n-3) - 224*a(n-4) + 92*a(n-5) - 12*a(n-6), for n >= 7.
G.f.: -(20*x^5-8*x^4+58*x^3-54*x^2+15*x-1) / ((x-1)*(2*x^2-4*x+1)*(6*x^3-28*x^2+13*x-1)). - Colin Barker, Nov 09 2015

Extensions

Definition edited by Eric M. Schmidt, Sep 17 2017

A292290 Number of vertices of type A at level n of the hyperbolic Pascal pyramid.

Original entry on oeis.org

0, 0, 3, 6, 12, 27, 66, 168, 435, 1134, 2964, 7755, 20298, 53136, 139107, 364182, 953436, 2496123, 6534930, 17108664, 44791059, 117264510, 307002468, 803742891, 2104226202, 5508935712, 14422580931, 37758807078, 98853840300, 258802713819, 677554301154
Offset: 0

Views

Author

Eric M. Schmidt, Sep 13 2017

Keywords

Crossrefs

Cf. A264236.

Programs

  • Mathematica
    CoefficientList[Series[3*x^2*(1 - 2*x)/((1 - x)*(1 - 3*x + x^2)), {x, 0, 30}], x] (* Wesley Ivan Hurt, Sep 17 2017 *)
  • PARI
    concat(vector(2), Vec(3*x^2*(1 - 2*x) / ((1 - x)*(1 - 3*x + x^2)) + O(x^30))) \\ Colin Barker, Sep 17 2017

Formula

a(n) = 4*a(n-1) - 4*a(n-2) + a(n-3), n >= 4.
From Colin Barker, Sep 17 2017: (Start)
G.f.: 3*x^2*(1 - 2*x) / ((1 - x)*(1 - 3*x + x^2)).
a(n) = 3*(1 + (2^(-1-n)*((7-3*sqrt(5))*(3+sqrt(5))^n - (3-sqrt(5))^n*(7+3*sqrt(5)))) / sqrt(5)) for n>0.
(End)
a(n) = 3*(Fibonacci(2*n - 4) + 1) for n > 0. - Ehren Metcalfe, Apr 18 2019

A292291 Number of vertices of type B at level n of the hyperbolic Pascal pyramid.

Original entry on oeis.org

0, 0, 0, 3, 12, 36, 99, 264, 696, 1827, 4788, 12540, 32835, 85968, 225072, 589251, 1542684, 4038804, 10573731, 27682392, 72473448, 189737955, 496740420, 1300483308, 3404709507, 8913645216, 23336226144, 61095033219, 159948873516, 418751587332, 1096305888483
Offset: 0

Views

Author

Eric M. Schmidt, Sep 13 2017

Keywords

Crossrefs

Cf. A264236.

Programs

  • Mathematica
    CoefficientList[Series[3*x^3/((1 - x)*(1 - 3*x + x^2)), {x, 0, 30}], x] (* Wesley Ivan Hurt, Sep 17 2017 *)
    LinearRecurrence[{4,-4,1},{0,0,0,3},40] (* Harvey P. Dale, Oct 25 2017 *)
  • PARI
    concat(vector(3), Vec(3*x^3 / ((1 - x)*(1 - 3*x + x^2)) + O(x^40))) \\ Colin Barker, Sep 17 2017

Formula

a(n) = 4*a(n-1) - 4*a(n-2) + a(n-3), n >= 4.
G.f.: 3*x^3 / ((1 - x)*(1 - 3*x + x^2)). - Colin Barker, Sep 17 2017
a(n) = 3*Fibonacci(2*n - 3) - 3 for n > 0. - Ehren Metcalfe, Apr 18 2019

A292292 Number of vertices of type C at level n of the hyperbolic Pascal pyramid.

Original entry on oeis.org

0, 0, 0, 1, 3, 9, 34, 174, 1128, 8251, 63315, 494175, 3879370, 30512736, 240149088, 1890487729, 14883249459, 117174190329, 922506823618, 7262871367566, 57180440473320, 450180590519275, 3544264121625315, 27903931958216271, 219687190433359498
Offset: 0

Views

Author

Eric M. Schmidt, Sep 13 2017

Keywords

Crossrefs

Cf. A264236.

Programs

  • Mathematica
    CoefficientList[Series[x^3*(1 - 9*x + 10*x^2)/((1 - x)*(1 - 8*x + x^2)*(1 - 3*x + x^2)), {x, 0, 30}], x] (* Wesley Ivan Hurt, Sep 17 2017 *)
  • PARI
    concat(vector(3), Vec(x^3*(1 - 9*x + 10*x^2) / ((1 - x)*(1 - 8*x + x^2)*(1 - 3*x + x^2)) + O(x^30))) \\ Colin Barker, Sep 17 2017

Formula

a(n) = 12*a(n-1) - 37*a(n-2) + 37*a(n-3) - 12*a(n-4) + a(n-5), n >= 6.
G.f.: x^3*(1 - 9*x + 10*x^2) / ((1 - x)*(1 - 8*x + x^2)*(1 - 3*x + x^2)). - Colin Barker, Sep 17 2017
a(n) = A001091(n-3)/15 + 3*A002878(n-3)/5 + 1/3 for n > 0. - Ehren Metcalfe, Apr 18 2019

A292293 Number of vertices of type D at level n of the hyperbolic Pascal pyramid.

Original entry on oeis.org

0, 0, 0, 0, 3, 24, 177, 1347, 10467, 82029, 644808, 5073915, 39939900, 314427960, 2475438408, 19488960504, 153435934587, 1207997701872, 9510543548457, 74876345104299, 589500202673403, 4641125238026805, 36539501601385200, 287674887310843395, 2264859596198883588
Offset: 0

Views

Author

Eric M. Schmidt, Sep 13 2017

Keywords

Crossrefs

Cf. A264236.

Programs

  • Mathematica
    CoefficientList[Series[3*x^4*(1 - 4*x)/((1 - x)*(1 - 8*x + x^2)*(1 - 3*x + x^2)), {x, 0, 30}], x] (* Wesley Ivan Hurt, Sep 17 2017 *)
  • PARI
    concat(vector(4), Vec(3*x^4*(1 - 4*x) / ((1 - x)*(1 - 8*x + x^2)*(1 - 3*x + x^2)) + O(x^30))) \\ Colin Barker, Sep 17 2017

Formula

a(n) = 12*a(n-1) - 37*a(n-2) + 37*a(n-3) - 12*a(n-4) + a(n-5), n >= 6.
G.f.: 3*x^4*(1 - 4*x) / ((1 - x)*(1 - 8*x + x^2)*(1 - 3*x + x^2)). - Colin Barker, Sep 17 2017

A292294 Number of vertices of type E at level n of the hyperbolic Pascal pyramid.

Original entry on oeis.org

0, 0, 0, 0, 3, 39, 357, 2952, 23622, 186984, 1474773, 11617815, 91485075, 720308160, 5671099008, 44648794944, 351520074867, 2767513935927, 21788596994037, 171541276628904, 1350541654293318, 10632792057873480, 83711795070905925, 659061569195852295
Offset: 0

Views

Author

Eric M. Schmidt, Sep 13 2017

Keywords

Crossrefs

Cf. A264236.

Programs

  • Mathematica
    CoefficientList[Series[3*x^4*(1 + x)/((1 - x)*(1 - 8*x + x^2)*(1 - 3*x + x^2)), {x, 0, 30}], x] (* Wesley Ivan Hurt, Sep 17 2017 *)
    LinearRecurrence[{12,-37,37,-12,1},{0,0,0,0,3,39},30] (* Harvey P. Dale, Oct 09 2018 *)
  • PARI
    concat(vector(4), Vec(3*x^4*(1 + x) / ((1 - x)*(1 - 8*x + x^2)*(1 - 3*x + x^2)) + O(x^30))) \\ Colin Barker, Sep 17 2017

Formula

a(n) = 12*a(n-1) - 37*a(n-2) + 37*a(n-3) - 12*a(n-4) + a(n-5), n >= 6.
G.f.: 3*x^4*(1 + x) / ((1 - x)*(1 - 8*x + x^2)*(1 - 3*x + x^2)). - Colin Barker, Sep 17 2017
a(n) = 1 + (A001091(n-2) - 3*Lucas(2*(2-n)))/5 for n > 0. - Ehren Metcalfe, Apr 18 2019
Showing 1-6 of 6 results.