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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A290901 p-INVERT of the positive integers, where p(S) = 1 - S^3 - S^4.

Original entry on oeis.org

0, 0, 1, 7, 29, 93, 260, 689, 1845, 5150, 14897, 43663, 127451, 368383, 1056682, 3022366, 8651672, 24818978, 71319058, 205070493, 589550733, 1694075057, 4866102091, 13975547842, 40139685023, 115298782211, 331216158188, 951506566087, 2733431466995
Offset: 0

Views

Author

Clark Kimberling, Aug 17 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 A290890 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x/(1 - x)^2; p = 1 - s^3 - s^4;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A000027 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1] (* A290901 *)
  • PARI
    concat(vector(2), Vec(x^2*(1 - x + x^2) / (1 - 8*x + 28*x^2 - 57*x^3 + 71*x^4 - 57*x^5 + 28*x^6 - 8*x^7 + x^8) + O(x^40))) \\ Colin Barker, Aug 18 2017

Formula

a(n) = 8*a(n-1) - 28*a(n-2) + 57*a(n-3) - 71*a(n-4) + 57*a(n-5) - 28*a(n-6) + 8*a(n-7) - a(n-8).
G.f.: x^2*(1 - x + x^2) / (1 - 8*x + 28*x^2 - 57*x^3 + 71*x^4 - 57*x^5 + 28*x^6 - 8*x^7 + x^8). - Colin Barker, Aug 18 2017

A290908 p-INVERT of the positive integers, where p(S) = 1 - 4*S^2.

Original entry on oeis.org

0, 4, 16, 56, 208, 780, 2912, 10864, 40544, 151316, 564720, 2107560, 7865520, 29354524, 109552576, 408855776, 1525870528, 5694626340, 21252634832, 79315912984, 296011017104, 1104728155436, 4122901604640, 15386878263120, 57424611447840, 214311567528244
Offset: 0

Views

Author

Clark Kimberling, Aug 17 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 A290890 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x/(1 - x)^2; p = 1 - 4 s^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A000027 *)
    u = Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1] (* A290908 *)
    u/4 (* A099486 *)

Formula

G.f.: (4 x)/(1 - 4 x + 2 x^2 - 4 x^3 + x^4).
a(n) = 4*a(n-1) - 2*a(n-2) + 4*a(n-3) - a(n-4).
a(n) = 4*A099486(n) for n >= 0.

A290919 p-INVERT of the positive integers, where p(S) = (1 - S)^4.

Original entry on oeis.org

4, 18, 72, 271, 976, 3398, 11516, 38179, 124272, 398248, 1259240, 3935420, 12173440, 37314700, 113452128, 342426657, 1026711724, 3059968146, 9069834488, 26748151221, 78518859336, 229505772002, 668173273988, 1938126895864, 5602502738380, 16143099833606
Offset: 0

Views

Author

Clark Kimberling, Aug 18 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 A290890 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x/(1 - x)^2; p = (1 - s)^4;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A000027 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A290919 *)

Formula

G.f.: (4 - 30 x + 88 x^2 - 125 x^3 + 88 x^4 - 30 x^5 + 4 x^6)/(1 - 3 x + x^2)^4.
a(n) = 12*a(n-1) - 58*a(n-2) + 144*a(n-3) - 195*a(n-4) + 144*a(n-5) - 58*a(n-6) + 12*a(n-7) - a(n-8).
(a(n)) is the p-INVERT of (1,1,1,1,1...) using p(S) = (1 - S - S^2)^4.

A290920 p-INVERT of the positive integers, where p(S) = (1 - S)^5.

Original entry on oeis.org

5, 25, 110, 450, 1746, 6505, 23465, 82435, 283270, 955258, 3169520, 10368490, 33497790, 107028120, 338582738, 1061557195, 3301399385, 10191612315, 31250047480, 95226980516, 288523285450, 869559080385, 2607834545025, 7785230674580, 23142279699355
Offset: 0

Views

Author

Clark Kimberling, Aug 18 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 A290890 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x/(1 - x)^2; p = (1 - s)^5;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A000027 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A290920 *)
  • PARI
    Vec((5 - 50*x + 210*x^2 - 475*x^3 + 621*x^4 - 475*x^5 + 210*x^6 - 50*x^7 + 5*x^8) / (1 - 3*x + x^2)^5 + O(x^30)) \\ Colin Barker, Aug 24 2017

Formula

a(n) = 15*a(n-1) - 95*a(n-2) + 330*a(n-3) - 685*a(n-4) + 873*a(n-5) - 695*a(n-6) + 330*a(n-7) - 95*a(n-8) + 15*a(n-9) - a(n-10).
G.f.: (5 - 50*x + 210*x^2 - 475*x^3 + 621*x^4 - 475*x^5 + 210*x^6 - 50*x^7 + 5*x^8) / (1 - 3*x + x^2)^5. - Colin Barker, Aug 24 2017

A290921 p-INVERT of the positive integers, where p(S) = (1 - S)^6.

Original entry on oeis.org

6, 33, 158, 696, 2886, 11425, 43590, 161355, 582340, 2056818, 7130388, 24319054, 81757104, 271353288, 890327048, 2891047695, 9299683770, 29658374355, 93843661530, 294791108106, 919849034686, 2852495485953, 8794877092878, 26971256457596, 82298545175130
Offset: 0

Views

Author

Clark Kimberling, Aug 18 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 A290890 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x/(1 - x)^2; p = (1 - s)^6;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A000027 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A290921 *)
  • PARI
    Vec((2 - x)*(1 - 2*x)*(1 - 5*x + 9*x^2 - 5*x^3 + x^4)*(3 - 15*x + 25*x^2 - 15*x^3 + 3*x^4) / (1 - 3*x + x^2)^6 + O(x^30)) \\ Colin Barker, Aug 24 2017

Formula

a(n) = 18*a(n-1) - 141*a(n-2) + 630*a(n-3) - 1770*a(n-4) + 3258*a(n-5) - 3989*a(n-6) + 3258*a(n-7) - 1770*a(n-8) + 630*a(n-9) - 141*a(n-10) + 18*a(n-11) - a(n-12).
G.f.: (2 - x)*(1 - 2*x)*(1 - 5*x + 9*x^2 - 5*x^3 + x^4)*(3 - 15*x + 25*x^2 - 15*x^3 + 3*x^4) / (1 - 3*x + x^2)^6. - Colin Barker, Aug 24 2017

A290922 p-INVERT of the positive integers, where p(S) = 1 - S - 2*S^2.

Original entry on oeis.org

1, 5, 20, 75, 279, 1040, 3881, 14485, 54060, 201755, 752959, 2810080, 10487361, 39139365, 146070100, 545141035, 2034494039, 7592835120, 28336846441, 105754550645, 394681356140, 1472970873915, 5497202139519, 20515837684160, 76566148597121, 285748756704325
Offset: 0

Views

Author

Clark Kimberling, Aug 18 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 A290890 for a guide to related sequences.

Crossrefs

Programs

  • Magma
    I:=[1,5,20,75]; [n le 4 select I[n] else 5*Self(n-1)- 6*Self(n-2)+5*Self(n-3)-Self(n-4): n in [1..30]]; // Vincenzo Librandi, Aug 19 2017
  • Mathematica
    z = 60; s = x/(1 - x)^2; p = 1 - s - 2 s^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A000027 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A290922 *)
    LinearRecurrence[{5, -6, 5, -1}, {1, 5, 20, 75}, 30] (* Vincenzo Librandi, Aug 19 2017 *)

Formula

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

A290925 p-INVERT of the positive integers, where p(S) = 1 - 3*S - 2*S^2.

Original entry on oeis.org

3, 17, 92, 495, 2661, 14304, 76891, 413329, 2221860, 11943663, 64203453, 345127232, 1855239875, 9972887313, 53609499612, 288179176047, 1549114207525, 8327301302176, 44763611772699, 240627889663761, 1293501104827044, 6953246818258415, 37377348295412093
Offset: 0

Views

Author

Clark Kimberling, Aug 19 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 A290890 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x/(1 - x)^2; p = 1 - 3 s - 2 s^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A000027 *)
    u = Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A290925 *)

Formula

G.f.: (3 - 4 x + 3 x^2)/(1 - 7 x + 10 x^2 - 7 x^3 + x^4).
a(n) = 7*a(n-1) - 10*a(n-2) + 7*a(n-3) - a(n-4).

A290926 p-INVERT of the positive integers, where p(S) = (1 - S^2)^2.

Original entry on oeis.org

0, 2, 8, 23, 64, 182, 520, 1475, 4152, 11624, 32408, 90028, 249272, 688140, 1894600, 5203665, 14260968, 39004962, 106486512, 290226621, 789776888, 2146082610, 5823823120, 15784464728, 42731452816, 115556460982, 312175750152, 842537682283, 2271900155120
Offset: 0

Views

Author

Clark Kimberling, Aug 19 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 A290890 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x/(1 - x)^2; p = (1 - s^2)^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A000027 *)
    u = Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A290926 *)

Formula

G.f.: (2 x - 8 x^2 + 11 x^3 - 8 x^4 + 2 x^5)/(1 - 4 x + 5 x^2 - 4 x^3 + x^4)^2.
a(n) = 8*a(n-1) - 26*a(n-2) + 48*a(n-3) - 59*a(n-4) + 48*a(n-5) - 26*a(n-6) + 8*a(n-7) - a(n-8).

A290927 p-INVERT of the positive integers, where p(S) = (1 - S^2)^3.

Original entry on oeis.org

0, 3, 12, 36, 108, 331, 1008, 3027, 8992, 26502, 77592, 225806, 653544, 1882224, 5396776, 15411399, 43847688, 124331457, 351448620, 990586686, 2784612380, 7808372811, 21845061504, 60983031772, 169897677504, 472435652577, 1311365875700, 3633925019190
Offset: 0

Views

Author

Clark Kimberling, Aug 19 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 A290890 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x/(1 - x)^2; p = (1 - s^2)^3;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A000027 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A290927 *)
  • PARI
    concat(0, Vec(x*(3 - 24*x + 81*x^2 - 156*x^3 + 193*x^4 - 156*x^5 + 81*x^6 - 24*x^7 + 3*x^8) / ((1 - 3*x + x^2)^3*(1 - x + x^2)^3) + O(x^30))) \\ Colin Barker, Aug 19 2017

Formula

a(n) = 12*a(n-1) - 63*a(n-2) + 196*a(n-3) - 414*a(n-4) + 636*a(n-5) - 731*a(n-6) + 636*a(n-7) - 414*a(n-8) + 196*a(n-9) - 63*a(n-10) + 12*a(n-11) - a(n-12).
G.f.: x*(3 - 24*x + 81*x^2 - 156*x^3 + 193*x^4 - 156*x^5 + 81*x^6 - 24*x^7 + 3*x^8) / ((1 - 3*x + x^2)^3*(1 - x + x^2)^3). - Colin Barker, Aug 19 2017

A290928 p-INVERT of the positive integers, where p(S) = (1 - S^3)^2.

Original entry on oeis.org

0, 0, 2, 12, 42, 115, 288, 738, 2020, 5751, 16362, 45697, 125538, 342318, 933050, 2547630, 6960042, 18990309, 51699042, 140439411, 380871538, 1031705466, 2792009100, 7548723827, 20389716864, 55020917232, 148334534420, 399562167420, 1075432476492
Offset: 0

Views

Author

Clark Kimberling, Aug 19 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 A290890 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x/(1 - x)^2; p = (1 - s^3)^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A000027 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A290928 *)
    LinearRecurrence[{12, -66, 222, -507, 822, -965, 822, -507, 222, -66, 12, -1}, {0, 0, 2, 12, 42, 115, 288, 738, 2020, 5751, 16362, 45697}, 40] (* Vincenzo Librandi, Aug 20 2017 *)
  • PARI
    concat(vector(2), Vec(x^2*(2 - 12*x + 30*x^2 - 41*x^3 + 30*x^4 - 12*x^5 + 2*x^6) / ((1 - 3*x + x^2)^2*(1 - 3*x + 5*x^2 - 3*x^3 + x^4)^2) + O(x^30))) \\ Colin Barker, Aug 19 2017

Formula

a(n) = 12*a(n-1) - 66*a(n-2) + 222*a(n-3) - 507*a(n-4) + 822*a(n-5) - 965*a(n-6) + 822*a(n-7) - 507*a(n-8) + 222*a(n-9) - 66*a(n-10) + 12*a(n-11) - a(n-12).
G.f.: x^2*(2 - 12*x + 30*x^2 - 41*x^3 + 30*x^4 - 12*x^5 + 2*x^6) / ((1 - 3*x + x^2)^2*(1 - 3*x + 5*x^2 - 3*x^3 + x^4)^2). - Colin Barker, Aug 19 2017
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