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.

User: Colin Barker

Colin Barker's wiki page.

Colin Barker has authored 805 sequences. Here are the ten most recent ones:

A317984 Expansion of 140*x*(1 + 4*x + x^2) / (1 - x)^5.

Original entry on oeis.org

140, 1260, 5040, 14000, 31500, 61740, 109760, 181440, 283500, 423500, 609840, 851760, 1159340, 1543500, 2016000, 2589440, 3277260, 4093740, 5054000, 6174000, 7470540, 8961260, 10664640, 12600000, 14787500, 17248140, 20003760, 23077040, 26491500, 30271500
Offset: 1

Author

Colin Barker, Aug 13 2018

Keywords

Comments

Seems to be the fourth column of A316387.

Crossrefs

Programs

  • PARI
    Vec(140*x*(1 + 4*x + x^2) / (1 - x)^5 + O(x^40))
    
  • PARI
    a(n) = 35*n^4 + 70*n^3 + 35*n^2

Formula

G.f.: 140*x*(1 + 4*x + x^2) / (1 - x)^5.
a(n) = 35*n^4 + 70*n^3 + 35*n^2.
a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5) for n>5.

A317983 Expansion of 420*x*(1 + x)*(1 + 10*x + x^2) / (1 - x)^6.

Original entry on oeis.org

420, 7140, 41160, 148680, 411180, 955500, 1963920, 3684240, 6439860, 10639860, 16789080, 25498200, 37493820, 53628540, 74891040, 102416160, 137494980, 181584900, 236319720, 303519720, 385201740, 483589260, 601122480, 740468400, 904530900, 1096460820
Offset: 1

Author

Colin Barker, Aug 13 2018

Keywords

Comments

Seems to be the negative of the third column of A316387.

Crossrefs

Programs

  • PARI
    Vec(420*x*(1 + x)*(1 + 10*x + x^2) / (1 - x)^6 + O(x^40))
    
  • PARI
    a(n) = 84*n^5 + 210*n^4 + 140*n^3 - 14*n

Formula

G.f.: 420*x*(1 + x)*(1 + 10*x + x^2) / (1 - x)^6.
a(n) = 420 * A000538(n).
a(n) = 84*n^5 + 210*n^4 + 140*n^3 - 14*n.
a(n) = 6*a(n-1) - 15*a(n-2) + 20*a(n-3) - 15*a(n-4) + 6*a(n-5) - a(n-6) for n>6.

A317982 Expansion of 14*x*(29 + 784*x + 1974*x^2 + 784*x^3 + 29*x^4) / (1 - x)^7.

Original entry on oeis.org

406, 13818, 115836, 545860, 1858290, 5124126, 12182968, 25945416, 50745870, 92745730, 160386996, 264896268, 420839146, 646725030, 965662320, 1406064016, 2002403718, 2796022026, 3835983340, 5179983060, 6895305186, 9059830318, 11763094056, 15107395800
Offset: 1

Author

Colin Barker, Aug 13 2018

Keywords

Comments

Seems to be the second column of A316387.

Crossrefs

Programs

  • Mathematica
    LinearRecurrence[{7,-21,35,-35,21,-7,1},{406,13818,115836,545860,1858290,5124126,12182968},30] (* Harvey P. Dale, Nov 15 2022 *)
  • PARI
    Vec(14*x*(29 + 784*x + 1974*x^2 + 784*x^3 + 29*x^4) / (1 - x)^7 + O(x^40))
    
  • PARI
    a(n) = 70*n^6 + 210*n^5 + 175*n^4 - 42*n^2 - 7*n

Formula

G.f.: 14*x*(29 + 784*x + 1974*x^2 + 784*x^3 + 29*x^4) / (1 - x)^7.
a(n) = 70*n^6 + 210*n^5 + 175*n^4 - 42*n^2 - 7*n.
a(n) = 7*a(n-1) - 21*a(n-2) + 35*a(n-3) - 35*a(n-4) + 21*a(n-5) - 7*a(n-6) + a(n-7) for n>7.

A317981 Expansion of x*(125 + 8028*x + 42237*x^2 + 42272*x^3 + 8007*x^4 + 132*x^5 - x^6) / (1 - x)^8.

Original entry on oeis.org

125, 9028, 110961, 684176, 2871325, 9402660, 25872833, 62572096, 136972701, 276971300, 524988145, 943023888, 1618774781, 2672907076, 4267591425, 6616398080, 9995653693, 14757360516, 21343778801, 30303773200, 42311023965, 58184203748, 78909220801
Offset: 1

Author

Colin Barker, Aug 13 2018

Keywords

Comments

Seems to be the negative of the first column of A316387.

Crossrefs

Programs

  • Mathematica
    LinearRecurrence[{8,-28,56,-70,56,-28,8,-1},{125,9028,110961,684176,2871325,9402660,25872833,62572096},30] (* Harvey P. Dale, Dec 29 2024 *)
  • PARI
    Vec(x*(125 + 8028*x + 42237*x^2 + 42272*x^3 + 8007*x^4 + 132*x^5 - x^6) / (1 - x)^8 + O(x^40))
    
  • PARI
    a(n) = 20*n^7 + 70*n^6 + 70*n^5 - 28*n^3 - 7*n^2

Formula

G.f.: x*(125 + 8028*x + 42237*x^2 + 42272*x^3 + 8007*x^4 + 132*x^5 - x^6) / (1 - x)^8.
a(n) = 20*n^7 + 70*n^6 + 70*n^5 - 28*n^3 - 7*n^2.
a(n) = 8*a(n-1) - 28*a(n-2) + 56*a(n-3) - 70*a(n-4) + 56*a(n-5) - 28*a(n-6) + 8*a(n-7) - a(n-8) for n>8.

A316459 Expansion of 30*x*(1 + x) / (1 - x)^4.

Original entry on oeis.org

30, 150, 420, 900, 1650, 2730, 4200, 6120, 8550, 11550, 15180, 19500, 24570, 30450, 37200, 44880, 53550, 63270, 74100, 86100, 99330, 113850, 129720, 147000, 165750, 186030, 207900, 231420, 256650, 283650, 312480, 343200, 375870, 410550, 447300, 486180
Offset: 1

Author

Colin Barker, Aug 12 2018

Keywords

Comments

Seems to be the third column of A316349.

Crossrefs

Programs

  • PARI
    Vec(30*x*(1 + x) / (1 - x)^4 + O(x^40))
    
  • PARI
    a(n) = 10*n^3 + 15*n^2 + 5*n

Formula

G.f.: 30*x*(1 + x) / (1 - x)^4.
a(n) = 30 * A000330(n).
a(n) = 10*n^3 + 15*n^2 + 5*n.
a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4) for n>4.

A316458 Expansion of 60*x*(1 + 4*x + x^2) / (1 - x)^5.

Original entry on oeis.org

60, 540, 2160, 6000, 13500, 26460, 47040, 77760, 121500, 181500, 261360, 365040, 496860, 661500, 864000, 1109760, 1404540, 1754460, 2166000, 2646000, 3201660, 3840540, 4570560, 5400000, 6337500, 7392060, 8573040, 9890160, 11353500, 12973500, 14760960
Offset: 1

Author

Colin Barker, Aug 12 2018

Keywords

Comments

Seems to be the negative of the second column of A316349.

Crossrefs

Programs

  • PARI
    Vec(60*x*(1 + 4*x + x^2) / (1 - x)^5 + O(x^40))
    
  • PARI
    a(n) = 15*n^4 + 30*n^3 + 15*n^2

Formula

G.f.: 60*x*(1 + 4*x + x^2) / (1 - x)^5.
a(n) = 60 * A000537(n).
a(n) = 15*n^4 + 30*n^3 + 15*n^2.
a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5) for n>5.

A316457 Expansion of x*(31 + 326*x + 336*x^2 + 26*x^3 + x^4) / (1 - x)^6.

Original entry on oeis.org

31, 512, 2943, 10624, 29375, 68256, 140287, 263168, 459999, 760000, 1199231, 1821312, 2678143, 3830624, 5349375, 7315456, 9821087, 12970368, 16879999, 21680000, 27514431, 34542112, 42937343, 52890624, 64609375, 78318656, 94261887, 112701568, 133919999
Offset: 1

Author

Colin Barker, Aug 12 2018

Keywords

Comments

Seems to be the first column of A316349.

Crossrefs

Programs

  • PARI
    Vec(x*(31 + 326*x + 336*x^2 + 26*x^3 + x^4) / (1 - x)^6 + O(x^40))
    
  • PARI
    a(n) = 6*n^5 + 15*n^4 + 10*n^3

Formula

G.f.: x*(31 + 326*x + 336*x^2 + 26*x^3 + x^4) / (1 - x)^6.
a(n) = 6*n^5 + 15*n^4 + 10*n^3.
a(n) = 6*a(n-1) - 15*a(n-2) + 20*a(n-3) - 15*a(n-4) + 6*a(n-5) - a(n-6) for n>6.

A299335 Expansion of 1 / ((1 - x)^7*(1 + x)^2).

Original entry on oeis.org

1, 5, 17, 45, 103, 211, 399, 707, 1190, 1918, 2982, 4494, 6594, 9450, 13266, 18282, 24783, 33099, 43615, 56771, 73073, 93093, 117481, 146965, 182364, 224588, 274652, 333676, 402900, 483684, 577524, 686052, 811053, 954465, 1118397, 1305129, 1517131, 1757063
Offset: 0

Author

Colin Barker, Feb 07 2018

Keywords

Crossrefs

Programs

  • Mathematica
    CoefficientList[Series[1/((1 - x)^7 (1 + x)^2), {x, 0, 40}], x] (* or *) LinearRecurrence[{5, -8, 0, 14, -14, 0, 8, -5, 1}, {1, 5, 17, 45, 103, 211, 399, 707, 1190}, 41] (* Robert G. Wilson v, Feb 07 2018 *)
  • PARI
    Vec(1 / ((1 - x)^7*(1 + x)^2) + O(x^40))

Formula

a(n) = (2*n^6 + 54*n^5 + 575*n^4 + 3060*n^3 + 8468*n^2 + 11376*n + 5760) / 5760 for n even.
a(n) = (2*n^6 + 54*n^5 + 575*n^4 + 3060*n^3 + 8468*n^2 + 11286*n + 5355) / 5760 for n odd.
a(n) = 5*a(n-1) - 8*a(n-2) + 14*a(n-4) - 14*a(n-5) + 8*a(n-7) - 5*a(n-8) + a(n-9) for n>8.

A299337 Expansion of 1 / ((1 - x)^7*(1 + x)^5).

Original entry on oeis.org

1, 2, 8, 14, 35, 56, 112, 168, 294, 420, 672, 924, 1386, 1848, 2640, 3432, 4719, 6006, 8008, 10010, 13013, 16016, 20384, 24752, 30940, 37128, 45696, 54264, 65892, 77520, 93024, 108528, 128877, 149226, 175560, 201894, 235543, 269192, 311696, 354200, 407330
Offset: 0

Author

Colin Barker, Feb 07 2018

Keywords

Crossrefs

Programs

  • Mathematica
    LinearRecurrence[{2, 4, -10, -5, 20, 0, -20, 5, 10, -4, -2, 1}, {1, 2, 8, 14, 35, 56, 112, 168, 294, 420, 672, 924}, 41] (* Michael De Vlieger, Dec 19 2024 *)
  • PARI
    Vec(1 / ((1 - x)^7*(1 + x)^5) + O(x^40))

Formula

a(n) = (2*n^6 + 72*n^5 + 1040*n^4 + 7680*n^3 + 30368*n^2 + 60288*n + 46080) / 46080 for n even.
a(n) = (2*n^6 + 72*n^5 + 1010*n^4 + 6960*n^3 + 24278*n^2 + 39048*n + 20790) / 46080 for n odd.
a(n) = 2*a(n-1) + 4*a(n-2) - 10*a(n-3) - 5*a(n-4) + 20*a(n-5) - 20*a(n-7) + 5*a(n-8) + 10*a(n-9) - 4*a(n-10) - 2*a(n-11) + a(n-12) for n>11.

A299338 Expansion of 1 / ((1 - x)^7*(1 + x)^6).

Original entry on oeis.org

1, 1, 7, 7, 28, 28, 84, 84, 210, 210, 462, 462, 924, 924, 1716, 1716, 3003, 3003, 5005, 5005, 8008, 8008, 12376, 12376, 18564, 18564, 27132, 27132, 38760, 38760, 54264, 54264, 74613, 74613, 100947, 100947, 134596, 134596, 177100, 177100, 230230, 230230
Offset: 0

Author

Colin Barker, Feb 07 2018

Keywords

Comments

Same as A000579 but with repeated terms.

Programs

  • Mathematica
    CoefficientList[Series[1/((1-x)^7(1+x)^6),{x,0,50}],x] (* or *) LinearRecurrence[ {1,6,-6,-15,15,20,-20,-15,15,6,-6,-1,1},{1,1,7,7,28,28,84,84,210,210,462,462,924},50] (* Harvey P. Dale, Oct 09 2018 *)
  • PARI
    Vec(1 / ((1 - x)^7*(1 + x)^6) + O(x^40))

Formula

a(n) = (2*n^6 + 84*n^5 + 1400*n^4 + 11760*n^3 + 51968*n^2 + 112896*n + 92160) / 92160 for n even.
a(n) = (2*n^6 + 72*n^5 + 1010*n^4 + 6960*n^3 + 24278*n^2 + 39048*n + 20790) / 92160 for n odd.
a(n) = a(n-1) + 6*a(n-2) - 6*a(n-3) - 15*a(n-4) + 15*a(n-5) + 20*a(n-6) - 20*a(n-7) - 15*a(n-8) + 15*a(n-9) + 6*a(n-10) - 6*a(n-11) - a(n-12) + a(n-13) for n>12.