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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A291385 a(n) = (1/4)*A073388(n+1).

Original entry on oeis.org

1, 4, 14, 47, 152, 480, 1488, 4548, 13744, 41152, 122272, 360944, 1059584, 3095552, 9005568, 26101824, 75404544, 217191424, 623928832, 1788071680, 5113137152, 14592352256, 41569120256, 118219097088, 335685021696, 951817715712, 2695241605120, 7622609858560
Offset: 0

Views

Author

Clark Kimberling, Sep 04 2017

Keywords

Crossrefs

Programs

  • Mathematica
    z = 60; s = x + x^2; p = (1 - 2 s)^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A019590 *)
    u = Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A073388 *)
    u / 2  (* A291385 *)
    LinearRecurrence[{4,0,-8,-4},{1,4,14,47},30] (* Harvey P. Dale, Aug 24 2022 *)

Formula

G.f.: -(((1 + x) (-1 + x + x^2))/(-1 + 2 x + 2 x^2)^2).
a(n) = 4*a(n-1) - 8*a(n-3) + 4*a(n-4) for n >= 5.
a(n) = Sum_{k=0..n+1} k * A155112(n+1,k). - Alois P. Heinz, Sep 29 2022

A291388 a(n) = (1/8)*A291387(n).

Original entry on oeis.org

1, 7, 44, 262, 1504, 8416, 46208, 250016, 1337088, 7083264, 37229568, 194383360, 1009172480, 5213634560, 26819756032, 137445318656, 702021435392, 3574958587904, 18156130926592, 91985567678464, 465004476235776, 2345955741401088, 11813573860786176
Offset: 0

Views

Author

Clark Kimberling, Sep 04 2017

Keywords

Crossrefs

Programs

  • GAP
    a:=8*[1,7,44,262];; for n in [5..10^2] do a[n]:=8*a[n-1]+-8*a[n-2]-32*a[n-3]-16*a[n-4]; od;
    A291388:=(1/8)*a;  # Muniru A Asiru, Sep 07 2017
  • Mathematica
    z = 60; s = x + x^2; p = (1 - 4 s)^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A019590 *)
    u = Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291387 *)
    u / 8  (* A291388 *)

Formula

G.f.: -(((1 + x) (-1 + 2 x + 2 x^2))/(-1 + 4 x + 4 x^2)^2).
a(n) = 8*a(n-1) - 8*a(n-2) - 32*a(n-3) - 16*a(n-4) for n >= 5.

A291390 a(n) = (1/5)*A291389(n).

Original entry on oeis.org

2, 17, 130, 940, 6550, 44475, 296250, 1944375, 12612500, 81035000, 516537500, 3270615625, 20591031250, 128998328125, 804673593750, 5000444062500, 30969644531250, 191231146484375, 1177627753906250, 7234317013671875, 44342955390625000, 271252632343750000
Offset: 0

Views

Author

Clark Kimberling, Sep 06 2017

Keywords

Crossrefs

Programs

  • Mathematica
    z = 60; s = x + x^2; p = (1 - 5 s)^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A019590 *)
    u = Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291389 *)
    u / 5  (* A291390 *)

Formula

G.f.: -(((1 + x) (-2 + 5 x + 5 x^2))/(-1 + 5 x + 5 x^2)^2).
a(n) = 10*a(n-1) - 15*a(n-2) - 50*a(n-3) - 25*a(n-4) for n >= 5.

A291392 a(n) = (1/12)*A291391(n).

Original entry on oeis.org

1, 10, 90, 765, 6264, 49968, 390960, 3013740, 22958640, 173225952, 1296640224, 9640743120, 71270772480, 524277204480, 3840015361536, 28018969060032, 203753553511680, 1477232299307520, 10681095982072320, 77040637862485248, 554445497303525376
Offset: 0

Views

Author

Clark Kimberling, Sep 06 2017

Keywords

Crossrefs

Programs

  • Mathematica
    z = 60; s = x + x^2; p = (1 - 6 s)^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A019590 *)
    u = Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291391 *)
    u / 12  (* A291392 *)
    LinearRecurrence[{12,-24,-72,-36},{1,10,90,765},30] (* Harvey P. Dale, Nov 24 2023 *)

Formula

G.f.: -(((1 + x) (-1 + 3 x + 3 x^2))/(-1 + 6 x + 6 x^2)^2).
a(n) = 12*a(n-1) - 24*a(n-2) - 72*a(n-3) - 36*a(n-4) for n >= 5.

A291393 p-INVERT of (1,1,0,0,0,0,...), where p(S) = (1 - S)(1 - 2 S).

Original entry on oeis.org

3, 10, 29, 83, 232, 643, 1771, 4862, 13321, 36455, 99696, 272535, 744839, 2035358, 5561381, 15195075, 41515496, 113425323, 309888403, 846638398, 2313071313, 6319448079, 17265085152, 47169141487, 128868574671, 352075628734, 961888724621, 2627929220939
Offset: 0

Views

Author

Clark Kimberling, Sep 06 2017

Keywords

Comments

Suppose s = (c(0), c(1), c(2), ...) is a sequence and p(S) is a polynomial. Let S(x) = c(0)*x + c(1)*x^2 + c(2)*x^3 + ... and T(x) = (-p(0) + 1/p(S(x)))/x. The p-INVERT of s is the sequence t(s) of coefficients in the Maclaurin series for T(x). Taking p(S) = 1 - S gives the "INVERT" transform of s, so that p-INVERT is a generalization of the "INVERT" transform (e.g., A033453).
See A291382 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x + x^2; p = (1 - s)(1 - 2s);
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A019590 *)
    u = Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291393 *)

Formula

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

A291394 p-INVERT of (1,1,0,0,0,0,...), where p(S) = (1 - S)(1 - 3 S).

Original entry on oeis.org

4, 17, 66, 254, 968, 3679, 13962, 52957, 200812, 761396, 2886768, 10944725, 41494856, 157319353, 596443614, 2261290498, 8573204920, 32503490435, 123230092830, 467200760741, 1771292578424, 6715480046152, 25460317920096, 96527393973769, 365963135802988
Offset: 0

Views

Author

Clark Kimberling, Sep 06 2017

Keywords

Comments

Suppose s = (c(0), c(1), c(2), ...) is a sequence and p(S) is a polynomial. Let S(x) = c(0)*x + c(1)*x^2 + c(2)*x^3 + ... and T(x) = (-p(0) + 1/p(S(x)))/x. The p-INVERT of s is the sequence t(s) of coefficients in the Maclaurin series for T(x). Taking p(S) = 1 - S gives the "INVERT" transform of s, so that p-INVERT is a generalization of the "INVERT" transform (e.g., A033453).
See A291382 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x + x^2; p = (1 - s)(1 - 3s);
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A019590 *)
    u = Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291394 *)

Formula

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

A291395 p-INVERT of (1,1,0,0,0,0,...), where p(S) = (1 - 2 S)(1 - 3 S).

Original entry on oeis.org

5, 24, 103, 425, 1704, 6715, 26153, 101052, 388303, 1486337, 5673840, 21616915, 82244873, 312603348, 1187325847, 4507385921, 17104894344, 64893555547, 246150297257, 933554883084, 3540272085535, 13424640644225, 50903370755040, 193007618806051, 731797403031305
Offset: 0

Views

Author

Clark Kimberling, Sep 06 2017

Keywords

Comments

Suppose s = (c(0), c(1), c(2), ...) is a sequence and p(S) is a polynomial. Let S(x) = c(0)*x + c(1)*x^2 + c(2)*x^3 + ... and T(x) = (-p(0) + 1/p(S(x)))/x. The p-INVERT of s is the sequence t(s) of coefficients in the Maclaurin series for T(x). Taking p(S) = 1 - S gives the "INVERT" transform of s, so that p-INVERT is a generalization of the "INVERT" transform (e.g., A033453).
See A291382 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x + x^2; p = (1 - 2s)(1 - 3s);
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A019590 *)
    u = Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291395 *)

Formula

G.f.: -(((1 + x) (-5 + 6 x + 6 x^2))/((-1 + 2 x + 2 x^2) (-1 + 3 x + 3 x^2))).
a(n) = 5*a(n-1) - a(n-2) - 12*a(n-3) - 6*a(n-4) for n >= 5.

A291396 p-INVERT of (1,1,0,0,0,0,...), where p(S) = (1 - S)(1 - 2 S)(1 - 3 S).

Original entry on oeis.org

6, 31, 140, 596, 2440, 9751, 38344, 149147, 575794, 2211278, 8460912, 32289105, 122994890, 467887343, 1778208080, 6753481344, 25636583768, 97283620659, 369070501684, 1399909005427, 5309251592646, 20133801242298, 76346423589984, 289487843638333
Offset: 0

Views

Author

Clark Kimberling, Sep 06 2017

Keywords

Comments

Suppose s = (c(0), c(1), c(2), ...) is a sequence and p(S) is a polynomial. Let S(x) = c(0)*x + c(1)*x^2 + c(2)*x^3 + ... and T(x) = (-p(0) + 1/p(S(x)))/x. The p-INVERT of s is the sequence t(s) of coefficients in the Maclaurin series for T(x). Taking p(S) = 1 - S gives the "INVERT" transform of s, so that p-INVERT is a generalization of the "INVERT" transform (e.g., A033453).
See A291382 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x + x^2; p = (1 - s)(1 - 2s)(1 - 3s);
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A019590 *)
    u = Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291396 *)

Formula

G.f.: -(((1 + x) (6 - 11 x - 5 x^2 + 12 x^3 + 6 x^4))/((-1 + x + x^2) (-1 + 2 x + 2 x^2) (-1 + 3 x + 3 x^2))).
a(n) = 6*a(n-1) - 5*a(n-2) - 16*a(n-3) + 7*a(n-4) + 18*a(n-5) + 6*a(n-6) for n >= 7.

A291397 p-INVERT of (1,1,0,0,0,0,...), where p(S) = 1 - S - S^3.

Original entry on oeis.org

1, 2, 4, 10, 22, 46, 97, 209, 452, 972, 2084, 4472, 9608, 20645, 44345, 95238, 204552, 439366, 943734, 2027046, 4353861, 9351633, 20086392, 43143592, 92668072, 199041584, 427521184, 918272425, 1972356577, 4236422746, 9099408124, 19544609858, 41979848918
Offset: 0

Views

Author

Clark Kimberling, Sep 06 2017

Keywords

Comments

Suppose s = (c(0), c(1), c(2), ...) is a sequence and p(S) is a polynomial. Let S(x) = c(0)*x + c(1)*x^2 + c(2)*x^3 + ... and T(x) = (-p(0) + 1/p(S(x)))/x. The p-INVERT of s is the sequence t(s) of coefficients in the Maclaurin series for T(x). Taking p(S) = 1 - S gives the "INVERT" transform of s, so that p-INVERT is a generalization of the "INVERT" transform (e.g., A033453).
See A291382 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x + x^2; p = 1 - s - s^3;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A019590 *)
    u = Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291397 *)

Formula

G.f.: -(((1 + x) (1 + x^2 + 2 x^3 + x^4))/((1 + x^2 + x^3) (-1 + x + 2 x^2 + x^3))).
a(n) = a(n-1) + a(n-2) + a(n-3) + 3*a(n-4) + 3*a(n-5) + a(n-6) for n >= 7.

A291398 p-INVERT of (1,1,0,0,0,0,...), where p(S) = 1 - S^2 - S^3.

Original entry on oeis.org

0, 1, 3, 5, 9, 19, 39, 76, 150, 301, 600, 1191, 2370, 4721, 9396, 18696, 37212, 74069, 147417, 293398, 583956, 1162257, 2313237, 4604037, 9163443, 18238042, 36299229, 72246487, 143792475, 286190708, 569606421, 1133689810, 2256387135, 4490895817, 8938246848
Offset: 0

Views

Author

Clark Kimberling, Sep 06 2017

Keywords

Comments

Suppose s = (c(0), c(1), c(2), ...) is a sequence and p(S) is a polynomial. Let S(x) = c(0)*x + c(1)*x^2 + c(2)*x^3 + ... and T(x) = (-p(0) + 1/p(S(x)))/x. The p-INVERT of s is the sequence t(s) of coefficients in the Maclaurin series for T(x). Taking p(S) = 1 - S gives the "INVERT" transform of s, so that p-INVERT is a generalization of the "INVERT" transform (e.g., A033453).
See A291382 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x + x^2; p = 1 - s^2 - s^3;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A019590 *)
    u = Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291398 *)
    LinearRecurrence[{0,1,3,4,3,1},{0,1,3,5,9,19},40] (* Harvey P. Dale, Dec 13 2017 *)

Formula

G.f.: -((x (1 + x)^2 (1 + x + x^2))/(-1 + x^2 + 3 x^3 + 4 x^4 + 3 x^5 + x^6)).
a(n) = a(n-2) + 3*a(n-3) + 4*a(n-4) + 3*a(n-5) + a(n-6) for n >= 7.
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