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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A289976 p-INVERT of (0,0,1,2,3,5,8,...), the Fibonacci numbers preceded by two zeros, where p(S) = 1 - S - S^2.

Original entry on oeis.org

0, 0, 1, 1, 2, 5, 9, 18, 36, 70, 137, 268, 522, 1017, 1980, 3852, 7492, 14568, 28321, 55051, 106999, 207952, 404134, 785366, 1526186, 2965752, 5763103, 11198858, 21761463, 42286357, 82169547, 159668921, 310262351, 602888757, 1171506956, 2276419286
Offset: 0

Views

Author

Clark Kimberling, Aug 21 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^3/(1 - x - x^2); p = 1 - s - s^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* 0,0,1,2,3,5,... *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A289976 *)

Formula

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

A290997 p-INVERT of (1,1,1,1,1,...), where p(S) = 1 - S^3 - S^6.

Original entry on oeis.org

0, 0, 1, 3, 6, 12, 27, 63, 143, 315, 684, 1479, 3195, 6903, 14932, 32361, 70266, 152775, 332397, 723330, 1573829, 3423444, 7444722, 16185939, 35185779, 76483890, 166253545, 361396431, 785621808, 1707884880, 3712912632, 8071922817, 17548551692, 38150905170
Offset: 0

Views

Author

Clark Kimberling, Aug 22 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 A291000 for a guide to related sequences.

Crossrefs

Programs

  • Magma
    R:=PowerSeriesRing(Integers(), 40); [0,0] cat Coefficients(R!( x^2*(1-3*x+3*x^2)/(1-6*x+15*x^2-21*x^3 + 18*x^4-9*x^5+x^6) )); // G. C. Greubel, Apr 14 2023
    
  • Mathematica
    z = 60; s = x/(1-x); p= 1 -s^3 -s^6;
    Drop[CoefficientList[Series[s, {x,0,z}], x], 1]  (* A000012 *)
    Drop[CoefficientList[Series[1/p, {x,0,z}], x], 1]  (* A290997 *)
    LinearRecurrence[{6,-15,21,-18,9,-1}, {0,0,1,3,6,12}, 40] (* G. C. Greubel, Apr 14 2023 *)
  • PARI
    concat(vector(2), Vec(x^2*(1-3*x+3*x^2)/(1-6*x+15*x^2-21*x^3 + 18*x^4-9*x^5+x^6) + O(x^50))) \\ Colin Barker, Aug 22 2017
    
  • SageMath
    def A290997_list(prec):
        P. = PowerSeriesRing(ZZ, prec)
        return P( x^2*(1-3*x+3*x^2)/(1-6*x+15*x^2-21*x^3 + 18*x^4-9*x^5+x^6) ).list()
    A290997_list(40) # G. C. Greubel, Apr 14 2023

Formula

a(n) = 6*a(n-1) - 15*a(n-2) + 21*a(n-3) - 18*a(n-4) + 9*a(n-5) - a(n-6) for n >= 7.
G.f.: x^2*(1 - 3*x + 3*x^2) / (1 - 6*x + 15*x^2 - 21*x^3 + 18*x^4 - 9*x^5 + x^6). - Colin Barker, Aug 22 2017

A289779 p-INVERT of the squares, where p(S) = 1 - S - S^2.

Original entry on oeis.org

1, 6, 28, 125, 546, 2371, 10304, 44838, 195209, 849896, 3700025, 16107530, 70121400, 305262325, 1328913506, 5785228011, 25185131956, 109639724218, 477300202625, 2077855302992, 9045633454817, 39378817534750, 171429815189636, 746294159430429, 3248880433597858
Offset: 0

Views

Author

Clark Kimberling, Aug 10 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 A289780 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = (x + x^2)/(1 - x)^3; p = 1 - s - s^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A000290 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1] (* A289779 *)

Formula

G.f.: (1 - x + 2 x^2 + 3 x^3 - x^4)/(1 - 7 x + 16 x^2 - 22 x^3 + 12 x^4 - 5 x^5 + x^6).
a(n) = 7*a(n-1) - 16*a(n-2) + 22*a(n-3) - 12*a(n-4) + 5*a(n-5) - a(n-6).

A289781 p-INVERT of the positive Fibonacci numbers (A000045), where p(S) = 1 - S - S^2.

Original entry on oeis.org

1, 3, 9, 27, 80, 237, 701, 2073, 6129, 18120, 53569, 158367, 468181, 1384083, 4091760, 12096453, 35760689, 105719157, 312537041, 923951760, 2731474161, 8075043963, 23872213729, 70573310907, 208635540400, 616788246957, 1823408134821, 5390532719313
Offset: 0

Views

Author

Clark Kimberling, Aug 10 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 A289780 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x/(1 - x - x^2); p = 1 - s - s^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A000045 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1] (* A289781 *)

Formula

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

A289785 p-INVERT of the (5^n), where p(S) = 1 - S - S^2.

Original entry on oeis.org

1, 7, 48, 325, 2183, 14588, 97161, 645719, 4285240, 28411789, 188257719, 1246893028, 8256349457, 54659946215, 361825274112, 2394939574997, 15851402375719, 104912178457996, 694343294142105, 4595323060281271, 30412598132972936, 201274210714545437
Offset: 0

Views

Author

Clark Kimberling, Aug 10 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 A289780 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x/(1 - 5*x); p = 1 - s - s^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A000351 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1] (* A289785 *)
  • PARI
    Vec(x*(1 - 4*x) / (1 - 11*x + 29*x^2) + O(x^30)) \\ Colin Barker, Aug 11 2017

Formula

G.f.: (1 - 4 x)/(1 - 11 x + 29 x^2).
a(n) = 11*a(n-1) - 29*a(n-2).
a(n) = (2^(-n-1)*((11-sqrt(5))^(n+1)*(-7+2*sqrt(5)) + (11+sqrt(5))^(n+1)*(7+2*sqrt(5)))) / (29*sqrt(5)). - Colin Barker, Aug 11 2017
a(n) = A081575(n+1)-4*A081575(n). - R. J. Mathar, Jul 08 2022

A289786 p-INVERT of the odd positive integers (A005408), where p(S) = 1 - S - S^2.

Original entry on oeis.org

1, 5, 20, 77, 291, 1098, 4149, 15689, 59332, 224369, 848447, 3208370, 12132345, 45878109, 173486772, 656035301, 2480778763, 9380993978, 35473960589, 134143768193, 507260826084, 1918192318185, 7253589435975, 27429241169378, 103722891648049, 392225150722037
Offset: 0

Views

Author

Clark Kimberling, Aug 10 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 A289780 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x (1 + x)/(1 - x)^2; p = 1 - s - s^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A005408 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1] (* A289786 *)
    LinearRecurrence[{5,-6,5,1},{1,5,20,77},30] (* Harvey P. Dale, May 06 2018 *)

Formula

G.f.: (-1 - x^2 - 2 x^3)/(-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).

A289788 a(n) = (1/2)*A289787(n).

Original entry on oeis.org

1, 6, 31, 156, 785, 3954, 19919, 100344, 505489, 2546430, 12827791, 64620756, 325530881, 1639881066, 8260997855, 41615265264, 209639359969, 1056070674294, 5320018479679, 26799907726860, 135006120168881, 680101314855906, 3426050596003631, 17258932500172776
Offset: 0

Views

Author

Clark Kimberling, Aug 10 2017

Keywords

Crossrefs

Programs

  • Mathematica
    z = 60; s = 2*x/(1 - x)^2; p = 1 - s - s^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A005843 *)
    u = Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1] (* A289787 *)
    u/2 (* A289788 *)

Formula

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

A289789 p-INVERT of A016777, where p(S) = 1 - S - S^2.

Original entry on oeis.org

1, 6, 26, 111, 460, 1905, 7910, 32880, 136675, 568050, 2360825, 9811650, 40777750, 169474875, 704348000, 2927312625, 12166086250, 50562982500, 210142784375, 873366003750, 3629761440625, 15085506018750, 62696266831250, 260569441284375, 1082942209562500
Offset: 0

Views

Author

Clark Kimberling, Aug 11 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 A289780 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x (1 + 2*x)/(1 - x)^2; p = 1 - s - s^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A016777 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1] (* A289789 *)

Formula

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

A289790 p-INVERT of A016789, where p(S) = 1 - S - S^2.

Original entry on oeis.org

2, 13, 72, 385, 2056, 11000, 58872, 315065, 1686086, 9023167, 48287964, 258415702, 1382925814, 7400803253, 39605804028, 211952630117, 1134276112400, 6070140759292, 32484690838716, 173843602765153, 930333564584074, 4978731041147699, 26643951936925764
Offset: 0

Views

Author

Clark Kimberling, Aug 12 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 A289780 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x (2 + x)/(1 - x)^2; p = 1 - s - s^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A016789 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1] (* A289790 *)

Formula

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

A289795 p-INVERT of (3n), where p(S) = 1 - S - S^2.

Original entry on oeis.org

3, 24, 162, 1083, 7260, 48681, 326406, 2188536, 14674041, 98388840, 659693103, 4423214952, 29657473194, 198852130383, 1333295304660, 8939689838877, 59940250397646, 401896898269128, 2694702070258437, 18067865859946320, 121144292846335179, 812267469938047224
Offset: 0

Views

Author

Clark Kimberling, Aug 12 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 A289780 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = 3*x/(1 - x)^2; p = 1 - s - s^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A008585 *)
    u = Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1] (* A289795 *)
    u/3  (* A289796 *)

Formula

G.f.: 3 (1 + x + x^2)/(1 - 7 x + 3 x^2 - 7 x^3 + x^4).
a(n) = 7*a(n-1) - 3*a(n-2) + 7*a(n-3) - a(n-4).
Previous Showing 11-20 of 81 results. Next