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 1-7 of 7 results.

A214198 Number of rooted planar binary unlabeled trees with n leaves and caterpillar index >= 3.

Original entry on oeis.org

0, 0, 0, 2, 4, 12, 36, 116, 384, 1304, 4504, 15772, 55832, 199432, 717816, 2600680, 9476800, 34710000, 127712560, 471851180, 1749864920, 6511643720, 24307501720, 91000873560, 341594374400, 1285436348112, 4848292800336, 18325541062936, 69405260675824, 263353613108944, 1001028051476656, 3811242180811728, 14533071892504448
Offset: 0

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Author

N. J. A. Sloane, Jul 07 2012

Keywords

Crossrefs

Programs

A214199 Number of rooted planar binary unlabeled trees with n leaves and caterpillar index = 3.

Original entry on oeis.org

0, 0, 0, 2, 0, 4, 12, 36, 120, 392, 1288, 4284, 14304, 48024, 162024, 548872, 1866416, 6368464, 21797776, 74822636, 257513344, 888439192, 3072153864, 10645835384, 36964041872, 128584760560, 448087042160, 1564065659608, 5467992829120, 19144550862960, 67123334707984, 235658063191312, 828405764175712, 2915610778184352, 10273466501139232, 36239527330228044
Offset: 0

Views

Author

N. J. A. Sloane, Jul 07 2012

Keywords

Crossrefs

Programs

A214200 Number of rooted planar binary unlabeled trees with n leaves and caterpillar index <= 4.

Original entry on oeis.org

0, 1, 1, 2, 5, 6, 26, 84, 269, 870, 2910, 9788, 33250, 114012, 394260, 1372776, 4809917, 16947462, 60012470, 213462380, 762355286, 2732658484, 9827926060, 35453715480, 128255260690, 465163021788, 1691086242796, 6161413737176, 22494722099492, 82282062468600, 301507924857768, 1106652847697872, 4068159345287325, 14976738917364166
Offset: 0

Views

Author

N. J. A. Sloane, Jul 07 2012

Keywords

Crossrefs

Programs

A214201 Number of rooted planar binary unlabeled trees with n leaves and caterpillar index >= 4.

Original entry on oeis.org

0, 0, 0, 0, 4, 8, 24, 80, 264, 912, 3216, 11488, 41528, 151408, 555792, 2051808, 7610384, 28341536, 105914784, 397028544, 1492351576, 5623204528, 21235347856, 80355038176, 304630332528, 1156851587552, 4400205758176, 16761475403328, 63937267846704, 244209062245984, 933904716768672, 3575584117620416, 13704666128328736, 52582688861676096
Offset: 0

Views

Author

N. J. A. Sloane, Jul 07 2012

Keywords

Crossrefs

Programs

A214202 Number of rooted planar binary unlabeled trees with n leaves and caterpillar index = 4.

Original entry on oeis.org

0, 0, 0, 0, 4, 0, 8, 32, 104, 352, 1264, 4480, 15992, 57408, 207152, 750144, 2725456, 9931328, 36282464, 132852224, 487443672, 1791742592, 6597006896, 24326190016, 89825979568, 332110462016, 1229345599520, 4555536068352, 16898439030192, 62743172964224, 233170424975072, 867250463225984, 3228189434389152, 12025362901992064, 44827564359795392
Offset: 0

Views

Author

N. J. A. Sloane, Jul 07 2012

Keywords

Crossrefs

Programs

  • Maple
    C:=(1-sqrt(1-4*x))/2; # A000108 with a different offset
    # F-(k): gives A025266, A025271, A214200, A214203
    Fm:=k->(1/2)*(1-sqrt(1-4*x+2^(k+1)*x^(k+1)));
    Sm:=k->seriestolist(series(Fm(k),x,50));
    # F+(k): gives A000108, A214198, A214201, A214204
    Fp:=k->C-Fm(k-1);
    Sp:=k->seriestolist(series(Fp(k),x,50));
    # F(k): gives A025266, A214199, A214202, A214205
    F:=k->Fm(k)-Fm(k-1);
    S:=k->seriestolist(series(F(k),x,50));
  • Mathematica
    (1/2)*(Sqrt[1 - 4*x + 16*x^4] - Sqrt[1 - 4*x + 32*x^5]) + O[x]^35 // CoefficientList[#, x]& (* Jean-François Alcover, Nov 07 2016, after Maple *)

A214203 Number of rooted planar binary unlabeled trees with n leaves and caterpillar index <= 5.

Original entry on oeis.org

0, 1, 1, 2, 5, 14, 26, 100, 333, 1110, 3742, 12764, 44258, 154636, 544660, 1932360, 6900029, 24780390, 89445174, 324326060, 1180834390, 4315287140, 15823305516, 58200045432, 214672363410, 793883691004, 2942917457772, 10933569255832, 40704185771812, 151826357818840, 567322837830824, 2123429246035600, 7960199797453213, 29884582184913542
Offset: 0

Views

Author

N. J. A. Sloane, Jul 07 2012

Keywords

Crossrefs

Programs

A214204 Number of rooted planar binary unlabeled trees with n leaves and caterpillar index >= 5.

Original entry on oeis.org

0, 0, 0, 0, 0, 8, 16, 48, 160, 560, 1952, 7008, 25536, 94000, 348640, 1301664, 4884928, 18410208, 69632320, 264176320, 1004907904, 3831461936, 14638340960, 56028848160, 214804352960, 824741125536, 3170860158656, 12205939334976, 47038828816512, 181465889281760, 700734291793600, 2708333654394432, 10476476693939584, 40557325959684032
Offset: 0

Views

Author

N. J. A. Sloane, Jul 07 2012

Keywords

Crossrefs

Programs

Showing 1-7 of 7 results.