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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A291038 p-INVERT of (1,0,0,1,0,0,1,0,0,...), where p(S) = (1 - 2 S)^2.

Original entry on oeis.org

4, 12, 32, 84, 216, 544, 1348, 3300, 8000, 19236, 45936, 109056, 257604, 605820, 1419232, 3313396, 7711944, 17900320, 41445764, 95746260, 220735616, 507934276, 1166792160, 2676017408, 6128381316, 14015556588, 32012831648, 73033858964, 166434905016
Offset: 0

Views

Author

Clark Kimberling, Sep 14 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 A291728 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x/(x - x^3); p = (1 - 2 s)^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A079978  *)
    u = Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291038 *)
    u/4 (* A291039 *)

Formula

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

A291723 p-INVERT of (1,0,1,0,0,0,0,...), where p(S) = 1 - S^3.

Original entry on oeis.org

0, 0, 1, 0, 3, 1, 3, 6, 2, 15, 9, 21, 36, 27, 85, 72, 141, 222, 231, 513, 540, 945, 1422, 1741, 3222, 3876, 6337, 9339, 12447, 20809, 27135, 42546, 62195, 86709, 136866, 187278, 286113, 417303, 595852, 910431, 1281810, 1926984, 2810883, 4064571, 6097464
Offset: 0

Views

Author

Clark Kimberling, Sep 08 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 A291728 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x + x^3; p = 1 - s^3;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A154272 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291723 *)
    LinearRecurrence[{0,0,1,0,3,0,3,0,1},{0,0,1,0,3,1,3,6,2},60] (* Harvey P. Dale, Jun 07 2022 *)

Formula

G.f.: -((x^2 (1 + x^2)^3)/((1 - x + x^2) (-1 + x + x^3) (1 + 2 x + 2 x^2 + x^3 + x^4))).
a(n) = a(n-3) + 3*a(n-5) + 3*a(n-7) + a(n-9) for n >= 10.

A291724 p-INVERT of (1,0,1,0,0,0,0,...), where p(S) = 1 - S^5.

Original entry on oeis.org

0, 0, 0, 0, 1, 0, 5, 0, 10, 1, 10, 10, 5, 45, 2, 120, 15, 210, 105, 253, 455, 230, 1365, 310, 3004, 1185, 5030, 4855, 6735, 15506, 8735, 38790, 17655, 77955, 56134, 130030, 178500, 195365, 481750, 327263, 1088225, 761775, 2095350, 2162550, 3593394, 5940325
Offset: 0

Views

Author

Clark Kimberling, Sep 08 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 A291728 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x + x^3; p = 1 - s^5;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A154272 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291724 *)
    LinearRecurrence[{0, 0, 0, 0, 1, 0, 5, 0, 10, 0, 10, 0, 5, 0, 1}, {0, 0, 0, 0, 1, 0, 5, 0, 10, 1, 10, 10, 5, 45, 2}, 50] (* Vincenzo Librandi, Sep 10 2017 *)

Formula

G.f.: -((x^4 (1 + x^2)^5)/((-1 + x + x^3) (1 + x + x^2 + 2 x^3 + 3 x^4 + 3 x^5 + 5 x^6 + 3 x^7 + 6 x^8 + x^9 + 4 x^10 + x^12))).
a(n) = a(n-5) + 5*a(n-7) + 10*a(n-9) + 10*a(n-11) + 5*a(n-13) + a(n-15) for n >= 15.

A291725 p-INVERT of (1,0,1,0,0,0,0,...), where p(S) = (1 - S)^2.

Original entry on oeis.org

2, 3, 6, 11, 18, 30, 50, 81, 130, 208, 330, 520, 816, 1275, 1984, 3077, 4758, 7337, 11286, 17322, 26532, 40563, 61908, 94336, 143540, 218112, 331008, 501749, 759726, 1149159, 1736534, 2621751, 3954826, 5960902, 8977686, 13511461, 20320854, 30542064, 45875998
Offset: 0

Views

Author

Clark Kimberling, Sep 08 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 A291728 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x + x^3; p = (1 - s)^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A154272 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291725 *)
    LinearRecurrence[{2, -1, 2, -2, 0, -1}, {2, 3, 6, 11, 18, 30}, 40] (* Vincenzo Librandi, Sep 10 2017 *)

Formula

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

A291726 p-INVERT of (1,0,1,0,0,0,0,...), where p(S) = (1 - S)^3.

Original entry on oeis.org

3, 6, 13, 27, 51, 94, 171, 303, 527, 906, 1539, 2586, 4308, 7122, 11692, 19077, 30957, 49986, 80349, 128628, 205146, 326058, 516594, 816076, 1285674, 2020380, 3167464, 4954887, 7734993, 12051616, 18743037, 29099781, 45106223, 69810162, 107887629, 166505313
Offset: 0

Views

Author

Clark Kimberling, Sep 08 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 A291728 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x + x^3; p = (1 - s)^3;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A154272 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291726 *)

Formula

G.f.: -(((1 + x^2) (3 - 3 x + x^2 - 3 x^3 + 2 x^4 + x^6))/(-1 + x + x^3)^3).
a(n) = 3*a(n-1) - 3*a(n-2) + 4*a(n-3) - 6*a(n-4) + 3*a(n-5) - 3*a(n-6) + 3*a(n-7) + a(n-9) for n >= 10.

A291727 p-INVERT of (1,0,1,0,0,0,0,...), where p(S) = (1 - S)^4.

Original entry on oeis.org

4, 10, 24, 55, 116, 234, 460, 879, 1640, 3006, 5424, 9650, 16964, 29510, 50852, 86893, 147360, 248198, 415440, 691428, 1144772, 1886270, 3094292, 5055140, 8227084, 13341756, 21564360, 34746331, 55823080, 89439056, 142928424, 227851285, 362396564, 575135150
Offset: 0

Views

Author

Clark Kimberling, Sep 08 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 A291728 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x + x^3; p = (1 - s)^4;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A154272 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291727 *)
    LinearRecurrence[{4,-6,8,-13,12,-10,12,-6,4,-4,0,-1},{4,10,24,55,116,234,460,879,1640,3006,5424,9650},40] (* Harvey P. Dale, Mar 13 2025 *)

Formula

G.f.: -(((-1 + x) (1 + x^2) (2 + x + x^2) (2 - 2 x + x^2 - 2 x^3 + 2 x^4 + x^6))/(-1 + x + x^3)^4).
a(n) = 4*a(n-1) - 6*a(n-2) + 8*a(n-3) - 13*a(n-4) + 12*a(n-5) - 10*a(n-6) + 12*a(n-7) - 6*a(n-8) +4*a(n-9) - 4*a(n-10) - a(n-12) for n >= 13.

A291729 p-INVERT of (1,0,1,0,0,0,0,...), where p(S) = 1 - 2 S - S^2.

Original entry on oeis.org

2, 5, 14, 39, 106, 290, 794, 2173, 5946, 16272, 44530, 121860, 333480, 912597, 2497400, 6834349, 18702782, 51181767, 140063294, 383295214, 1048920220, 2870460125, 7855260268, 21496593296, 58827270844, 160985870984, 440551640160, 1205607339709, 3299247863502
Offset: 0

Views

Author

Clark Kimberling, Sep 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 A291728 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x + x^3; p = 1 - 2 s - s^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A154272 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291729 *)

Formula

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

A291731 a(n) = (1/2)*A291730(n).

Original entry on oeis.org

1, 3, 9, 28, 84, 255, 772, 2340, 7088, 21476, 65064, 197126, 597228, 1809420, 5481980, 16608712, 50319264, 152451844, 461882016, 1399359936, 4239628608, 12844765920, 38915675520, 117902483528, 357208128400, 1082230358448, 3278823900048, 9933824239744
Offset: 0

Views

Author

Clark Kimberling, Sep 11 2017

Keywords

Crossrefs

Programs

  • Mathematica
    z = 60; s = x + x^3; p = 1 - 2 s - 2 s^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A154272 *)
    u = Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291730 *)
    u / 2  (* A291731 *)

Formula

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

A291733 a(n) = (1/4)*A291732(n).

Original entry on oeis.org

1, 3, 9, 26, 72, 195, 520, 1368, 3560, 9184, 23520, 59860, 151536, 381840, 958256, 2396192, 5972736, 14845040, 36801792, 91021056, 224642304, 553347072, 1360598016, 3340024384, 8186748160, 20038426368, 48983457024, 119593531904, 291657627648, 710522702592
Offset: 0

Views

Author

Clark Kimberling, Sep 11 2017

Keywords

Crossrefs

Programs

  • Mathematica
    z = 60; s = x + x^3; p = (1 - 2 s)^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A154272 *)
    u = Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291732 *)
    u / 4  (*A291733)

Formula

G.f.: -(((1 + x^2) (-1 + x + x^3))/(-1 + 2 x + 2 x^3)^2).
a(n) = 4*a(n-1) - 4*a(n-2) + 4*a(n-3) - 8*a(n-4) - 4*a(n-6) for n >= 7.

A291734 p-INVERT of (1,0,1,0,0,0,0,...), where p(S) = (1 - S)(1 - 2 S).

Original entry on oeis.org

3, 7, 18, 45, 108, 258, 615, 1459, 3453, 8164, 19287, 45540, 107496, 253695, 598659, 1412587, 3332970, 7863853, 18553752, 43774722, 103279023, 243668295, 574890057, 1356344056, 3200033343, 7549859464, 17812425600, 42024945087, 99149648967, 233924207559
Offset: 0

Views

Author

Clark Kimberling, Sep 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 A291728 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x + x^3; p = (1 - s) (1 - 2 s);
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A154272 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291734 *)

Formula

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