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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A291399 p-INVERT of (1,1,0,0,0,0,...), where p(S) = 1 - S - S^2 - S^3 - S^4.

Original entry on oeis.org

1, 3, 8, 22, 59, 156, 412, 1093, 2903, 7707, 20453, 54275, 144035, 382255, 1014469, 2692284, 7144989, 18961928, 50322686, 133550412, 354426839, 940606403, 2496256771, 6624766692, 17581338025, 46658767166, 123826784175, 328621466028, 872122042693
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^2 - s^3 - s^4;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A019590 *)
    u = Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291399 *)
    LinearRecurrence[{1,2,3,5,7,7,4,1},{1,3,8,22,59,156,412,1093},40] (* Harvey P. Dale, Oct 06 2018 *)

Formula

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

A291400 p-INVERT of (1,1,0,0,0,0,...), where p(S) = 1 - S^2 - S^4.

Original entry on oeis.org

0, 1, 2, 3, 8, 15, 26, 52, 100, 193, 378, 726, 1396, 2699, 5210, 10065, 19444, 37528, 72448, 139890, 270104, 521547, 1007026, 1944336, 3754132, 7248558, 13995676, 27023186, 52176848, 100743849, 194517966, 375578833, 725174524, 1400180233, 2703493026
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^4;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A019590 *)
    u = Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291400 *)

Formula

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

A291401 p-INVERT of (1,1,0,0,0,0,...), where p(S) = 1 - S - S^4.

Original entry on oeis.org

1, 2, 3, 6, 14, 32, 67, 134, 266, 538, 1110, 2304, 4760, 9770, 19991, 40931, 83976, 172519, 354452, 727830, 1493768, 3065341, 6291208, 12914136, 26511196, 54423052, 111715200, 229312168, 470697488, 966192481, 1983312305, 4071174986, 8356928055, 17154242334
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^4;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A019590 *)
    u = Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291401 *)

Formula

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

A291402 p-INVERT of (1,1,0,0,0,0,...), where p(S) = 1 - S^3 - S^4.

Original entry on oeis.org

0, 0, 1, 4, 7, 8, 12, 31, 71, 125, 201, 367, 749, 1471, 2679, 4814, 9014, 17304, 32739, 60683, 112444, 210938, 397800, 746347, 1392898, 2601701, 4876692, 9149911, 17138518, 32060349, 60002060, 112404852, 210600344, 394370928, 738281497, 1382360598
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^3 - s^4;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A019590 *)
    u = Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291402 *)
    LinearRecurrence[{0,0,1,4,7,7,4,1},{0,0,1,4,7,8,12,31},40] (* Harvey P. Dale, Feb 20 2020 *)

Formula

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

A291403 p-INVERT of (1,1,0,0,0,0,...), where p(S) = 1 - 2 S^2 - S^4.

Original entry on oeis.org

0, 2, 4, 7, 20, 42, 92, 214, 472, 1062, 2396, 5361, 12052, 27074, 60764, 136497, 306520, 688292, 1545768, 3471224, 7795184, 17505588, 39311608, 88280985, 198250312, 445204610, 999783508, 2245185343, 5041947516, 11322557726, 25426742788, 57100105470
Offset: 0

Views

Author

Clark Kimberling, Sep 07 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 - 2 s^2 - s^4;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A019590 *)
    u = Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291403 *)

Formula

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

A291404 p-INVERT of (1,1,0,0,0,0,...), where p(S) = 1 - S^2 - 2 S^4.

Original entry on oeis.org

0, 1, 2, 4, 12, 23, 42, 89, 188, 404, 856, 1763, 3652, 7641, 16030, 33612, 70252, 146623, 306334, 640637, 1340024, 2802056, 5857264, 12243403, 25596040, 53515853, 111889138, 233922392, 489039852, 1022399607, 2137493106, 4468804953, 9342779572, 19532522316
Offset: 0

Views

Author

Clark Kimberling, Sep 07 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 - 2 s^4;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A019590 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291404 *)

Formula

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

A291406 a(n) = (1/2)A291405(n).

Original entry on oeis.org

0, 1, 2, 4, 12, 26, 60, 145, 336, 796, 1880, 4412, 10400, 24488, 57648, 135794, 319744, 752908, 1773016, 4175032, 9831472, 23151400, 54516976, 128377380, 302304640, 711870368, 1676321856, 3947423264, 9295440640, 21889019712, 51544533376, 121377706184
Offset: 0

Views

Author

Clark Kimberling, Sep 07 2017

Keywords

Crossrefs

Programs

  • Mathematica
    z = 60; s = x + x^2; p = 1 - 2 s^2 - 2 s^4;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A019590 *)
    u = Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291405 *)
    u / 2 (* A291406 *)

Formula

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

A291407 p-INVERT of (1,1,0,0,0,0,...), where p(S) = 1 - S^3 - S^6.

Original entry on oeis.org

0, 0, 1, 3, 3, 3, 12, 30, 43, 57, 120, 259, 438, 708, 1360, 2703, 4827, 8276, 15114, 28488, 51769, 92031, 167334, 309341, 564237, 1016487, 1844115, 3374343, 6151563, 11151098, 20253876, 36931695, 67280308, 122243430, 222174201, 404488108, 736378968
Offset: 0

Views

Author

Clark Kimberling, Sep 07 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^3 - s^6;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A019590 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291407 *)

Formula

G.f.: -((x^2 (1 + x)^3 (1 + x + x^2) (1 - x + 2 x^3 + x^4))/(-1 + x^3 + 3 x^4 + 3 x^5 + 2 x^6 + 6 x^7 + 15 x^8 + 20 x^9 + 15 x^10 + 6 x^11 + x^12)).
a(n) = a(n-3) + 3*a(n-4) + 3*a(n-5) + 2*a(n-6) + 6*a(n-7) + 15*a(n-8) + 20*a(n-9) + 15*a(n-10) + 6*a(n-11) + a(n-12) for n >= 13.

A291409 p-INVERT of (1,1,0,0,0,0,...), where p(S) = (1 - S^2)(1 - S)^2.

Original entry on oeis.org

2, 6, 14, 31, 66, 136, 272, 534, 1030, 1958, 3678, 6837, 12594, 23016, 41768, 75325, 135084, 241032, 428112, 757236, 1334292, 2342892, 4100676, 7155937, 12453170, 21616242, 37432010, 64675099, 111512574, 191893120, 329605760, 565166682, 967491754, 1653659282
Offset: 0

Views

Author

Clark Kimberling, Sep 07 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)(1 - s)^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A019590 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291409 *)
    LinearRecurrence[{2,2,-2,-5,-2,4,4,1},{2,6,14,31,66,136,272,534},40] (* Harvey P. Dale, May 12 2024 *)

Formula

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

A291410 p-INVERT of (1,1,0,0,0,0,...), where p(S) = 1 - S - S^2 - 2 S^3.

Original entry on oeis.org

1, 3, 9, 26, 69, 186, 511, 1401, 3824, 10438, 28521, 77938, 212928, 581700, 1589231, 4341911, 11862339, 32408429, 88541424, 241899801, 660882666, 1805564823, 4932894579, 13476918898, 36819627664, 100593093135, 274825440378, 750837066710, 2051325016200
Offset: 0

Views

Author

Clark Kimberling, Sep 07 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

  • GAP
    a:=[1,3,9,26,69,186];;  for n in [7..10^2] do a[n]:=a[n-1]+2*a[n-2]+4*a[n-3]+7*a[n-4]+6*a[n-5]+2*a[n-6]; od; a; # Muniru A Asiru, Sep 12 2017
  • Mathematica
    z = 60; s = x + x^2; p = 1 - s - s^2 - 2 s^3;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A019590 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291410 *)
    CoefficientList[ Series[-(2x^5 +6x^4 +7x^3 +4x^2 +2x +1)/(2x^6 +6x^5 +7x^4 +4x^3 +2x^2 +x- 1), {x, 0, 28}], x] (* or *)
    LinearRecurrence[{1, 2, 4, 7, 6, 2}, {1, 3, 9, 26, 69, 186}, 29] (* Robert G. Wilson v, Sep 25 2017 *)

Formula

G.f.: -(((1 + x) (1 + x + 3 x^2 + 4 x^3 + 2 x^4))/((-1 + 2 x + 2 x^2) (1 + x + 2 x^2 + 2 x^3 + x^4))).
a(n) = a(n-1) + 2*a(n-2) + 4*a(n-3) + 7*a(n-4) + 6*a(n-5) + 2*a(n-6) for n >= 7.
Previous Showing 21-30 of 40 results. Next