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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A291001 p-INVERT of (1,1,1,1,1,...), where p(S) = 1 - 8*S^2.

Original entry on oeis.org

0, 8, 16, 88, 288, 1192, 4400, 17144, 65088, 250184, 955984, 3663256, 14018400, 53679592, 205487984, 786733112, 3011882112, 11530896008, 44144966800, 169006205656, 647027178912, 2477097797416, 9483385847216, 36306456276344, 138996613483200, 532138420900808
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
    [n le 2 select 8*(n-1) else 2*Self(n-1) +7*Self(n-2): n in [1..41]]; // G. C. Greubel, Apr 25 2023
    
  • Mathematica
    z = 60; s = x/(1 - x); p = 1 - s^8;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A000012 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291001 *)
    LinearRecurrence[{2,7}, {0,8}, 41] (* G. C. Greubel, Apr 25 2023 *)
  • SageMath
    A291001=BinaryRecurrenceSequence(2,7,0,8)
    [A291001(n) for n in range(41)] # G. C. Greubel, Apr 25 2023

Formula

G.f.: 8*x/(1 - 2*x - 7*x^2).
a(n) = 2*a(n-1) + 7*a(n-2) for n >= 3.
a(n) = 8*A015519(n).
a(n) = sqrt(2)*((1+2*sqrt(2))^n - (1-2*sqrt(2))^n). - Colin Barker, Aug 23 2017

A291002 p-INVERT of (1,1,1,1,1,...), where p(S) = (1 - S)*(1 - 2*S)*(1 - 3*S).

Original entry on oeis.org

6, 31, 146, 652, 2816, 11896, 49496, 203752, 832376, 3381736, 13683896, 55206952, 222242936, 893219176, 3585623096, 14380739752, 57637717496, 230895178216, 924613703096, 3701553914152, 14815513224056, 59289946122856, 237243465219896, 949224905162152
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
    [(2^n-16*3^n+27*4^n)/2: n in [0..40]]; // G. C. Greubel, Apr 27 2023
    
  • Mathematica
    z = 60; s = x/(1-x); p = (1-s)*(1-2*s)*(1-3*s);
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A000012 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291002 *)
    LinearRecurrence[{9,-26,24}, {6,31,146}, 41] (* G. C. Greubel, Apr 27 2023 *)
  • SageMath
    [(2^n-16*3^n+27*4^n)/2 for n in range(41)] # G. C. Greubel, Apr 27 2023

Formula

G.f.: (6 - 23*x + 23*x^2)/(1 - 9*x + 26*x^2 - 24*x^3).
a(n) = 9*a(n-1) - 26*a(n-2) + 24*a(n-3) for n >= 4.
a(n) = (2^n - 16*3^n + 27*4^n) / 2. - Colin Barker, Aug 23 2017
E.g.f.: (1/2)*(exp(2*x) - 16*exp(3*x) + 27*exp(4*x)). - G. C. Greubel, Apr 27 2023

A291003 p-INVERT of (1,1,1,1,1,...), where p(S) = (1 - S)(1 - 2*S)(1 - 3*S)(1 - 4*S).

Original entry on oeis.org

10, 75, 490, 2956, 16944, 93800, 506600, 2687256, 14064904, 72873880, 374671560, 1914880856, 9741440264, 49378177560, 249583291720, 1258711575256, 6336814854024, 31857331730840, 159980377179080, 802678826106456, 4024508089842184, 20167014882109720
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
    [(-2^n +48*3^n -243*4^n +256*5^n)/6: n in [0..40]]; // G. C. Greubel, May 23 2023
    
  • Mathematica
    z = 60; s = x/(1-x); p = (1 - s)(1 - 2 s)(1 - 3 s)(1 - 4 s);
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A000012 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291003 *)
    LinearRecurrence[{14,-71,154,-120}, {10,75,490,2956}, 41] (* G. C. Greubel, May 23 2023 *)
  • SageMath
    [(-2^n +48*3^n -243*4^n +256*5^n)//6 for n in range(41)] # G. C. Greubel, May 23 2023

Formula

G.f.: (10 - 65*x + 150*x^2 - 119*x^3)/(1 - 14*x + 71*x^2 - 154*x^3 + 120*x^4).
a(n) = 14*a(n-1) - 71*a(n-2) + 154*a(n-3) - 120*a(n-4) for n >= 5.
a(n) = (-2^n + 16*3^(1+n) - 243*4^n + 256*5^n) / 6. - Colin Barker, Aug 23 2017

A291004 p-INVERT of (1,1,1,1,1,...), where p(S) = (1 - 3*S)^2.

Original entry on oeis.org

6, 33, 168, 816, 3840, 17664, 79872, 356352, 1572864, 6881280, 29884416, 128974848, 553648128, 2365587456, 10066329600, 42681237504, 180388626432, 760209211392, 3195455668224, 13400297963520, 56075093016576, 234195976716288, 976366325465088, 4063794976260096
Offset: 0

Views

Author

Clark Kimberling, Aug 23 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
    [3*(4^(n-1)*(3*n+8)): n in [0..30]]; // Vincenzo Librandi, Aug 27 2017
    
  • Mathematica
    z = 60; s = x/(1-x); p = (1 - 3 s)^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A000012 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291004 *)
    LinearRecurrence[{8, -16}, {6, 33}, 25] (* Vincenzo Librandi, Aug 27 2017 *)
  • SageMath
    [3*4^n*(3*n+8)//4 for n in range(41)] # G. C. Greubel, Jun 01 2023

Formula

G.f.: 3*(2 - 5*x)/(1 - 4*x)^2.
a(n) = 8*a(n-1) - 16*a(n-2) for n >= 3.
a(n) = 3*A006234(n+3) for n >= 0.
a(n) = 3 * 4^(n-1) * (3*n+8). - Colin Barker, Aug 23 2017

A291005 p-INVERT of (1,1,1,1,1,...), where p(S) = 1 - 2 S - 2 S^3.

Original entry on oeis.org

2, 6, 20, 68, 230, 774, 2600, 8732, 29330, 98526, 330980, 1111868, 3735110, 12547374, 42150440, 141596132, 475664450, 1597901526, 5367837140, 18032197268, 60575633990, 203491974774, 683591422280, 2296391457932, 7714277207570, 25914602943726, 87055031555300
Offset: 0

Views

Author

Clark Kimberling, Aug 23 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
    I:=[2,6,20]; [n le 3 select I[n] else 5*Self(n-1)-7*Self(n-2)+5*Self(n-3): n in [1..30]]; // Vincenzo Librandi, Aug 27 2017
    
  • Mathematica
    z = 60; s = 1 - 2 s - 2 s^3;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A000012 *)
    u = Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291005 *)
    u / 2  (* A291337 *)
    LinearRecurrence[{5, -7, 5}, {2, 6, 20}, 30] (* Vincenzo Librandi, Aug 27 2017 *)
  • SageMath
    def A291005_list(prec):
        P. = PowerSeriesRing(ZZ, prec)
        return P( 2*(1-2*x+2*x^2)/(1-5*x+7*x^2-5*x^3) ).list()
    A291005_list(30) # G. C. Greubel, Jun 01 2023

Formula

G.f.: 2*(1 - 2*x + 2*x^2)/(1 - 5*x + 7*x^2 - 5*x^3).
a(n) = 5*a(n-1) - 7*a(n-2) + 5*a(n-3) for n >= 4.
a(n) = 2*A291337(n) for n >= 0.

A291006 p-INVERT of (1,1,1,1,1,...), where p(S) = 1 - S - S^2 - S^3 - S^4.

Original entry on oeis.org

1, 3, 9, 27, 80, 235, 688, 2013, 5891, 17244, 50482, 147791, 432672, 1266680, 3708288, 10856241, 31782309, 93044665, 272394011, 797450348, 2334585333, 6834643282, 20008841823, 58577124509, 171488162320, 502042223184, 1469759722591, 4302812676894
Offset: 0

Views

Author

Clark Kimberling, Aug 23 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); Coefficients(R!( (1-2*x+2*x^2)/(1-5*x+8*x^2-6*x^3+x^4) )); // G. C. Greubel, Jun 01 2023
    
  • Mathematica
    z = 60; s = x/(1 - x); p = 1 - s - s^2 - s^3 - s^4;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A000012 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291006 *)
    LinearRecurrence[{5,-8,6,-1}, {1,3,9,27}, 41] (* G. C. Greubel, Jun 01 2023 *)
  • SageMath
    def A291006_list(prec):
        P. = PowerSeriesRing(ZZ, prec)
        return P( (1-2*x+2*x^2)/(1-5*x+8*x^2-6*x^3+x^4) ).list()
    A291006_list(40) # G. C. Greubel, Jun 01 2023

Formula

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

A291007 p-INVERT of (1,1,1,1,1,...), where p(S) = 1 - S - S^2 - S^3 - S^4 - S^5.

Original entry on oeis.org

1, 3, 9, 27, 81, 242, 720, 2137, 6337, 18789, 55715, 165232, 490058, 1453493, 4311025, 12786359, 37923789, 112480082, 333610072, 989469949, 2934716101, 8704215281, 25816251319, 76569665176, 227101665034, 673571786617, 1997779058053, 5925309279179
Offset: 0

Views

Author

Clark Kimberling, Aug 23 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); Coefficients(R!( (1 -3*x +4*x^2 -2*x^3 +x^4)/(1 -6*x +13*x^2 -14*x^3 +7*x^4 -2*x^5) )); // G. C. Greubel, Jun 01 2023
    
  • Mathematica
    z = 60; s = x/(1 - x); p = 1 - s - s^2 - s^3 - s^4 - s^5;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A000012 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291007 *)
    LinearRecurrence[{6,-13,14,-7,2},{1,3,9,27,81},30] (* Harvey P. Dale, Apr 07 2019 *)
  • PARI
    Vec((1 -3*x +4*x^2 -2*x^3 +x^4)/(1 -6*x +13*x^2 -14*x^3 +7*x^4 - 2*x^5) + O(x^30)) \\ Colin Barker, Aug 23 2017
    
  • SageMath
    def A291007_list(prec):
        P. = PowerSeriesRing(ZZ, prec)
        return P( (1 -3*x +4*x^2 -2*x^3 +x^4)/(1 -6*x +13*x^2 -14*x^3 +7*x^4 -2*x^5) ).list()
    A291007_list(40) # G. C. Greubel, Jun 01 2023

Formula

a(n) = 6*a(n-1) - 13*a(n-2) + 14*a(n-3) - 7*a(n-4) + 2*a(n-5) for n >= 6.
G.f.: (1 - 3*x + 4*x^2 - 2*x^3 + x^4) / (1 - 6*x + 13*x^2 - 14*x^3 + 7*x^4 - 2*x^5). - Colin Barker, Aug 23 2017

A291009 p-INVERT of (1,1,1,1,1,...), where p(S) = (1 - S)*(1 - 3*S).

Original entry on oeis.org

4, 17, 70, 284, 1144, 4592, 18400, 73664, 294784, 1179392, 4718080, 18873344, 75495424, 301985792, 1207951360, 4831821824, 19327320064, 77309345792, 309237514240, 1236950319104, 4947801800704, 19791208251392, 79164835102720, 316659344605184, 1266637386809344
Offset: 0

Views

Author

Clark Kimberling, Aug 23 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
    [2^(n-1)*(9*2^n -1): n in [0..40]]; // G. C. Greubel, Jun 04 2023
    
  • Mathematica
    z = 60; s = x/(1-x); p = (1-s)(1-3s);
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A000012 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1] (* A291009 *)
    LinearRecurrence[{6,-8}, {4,17}, 40] (* G. C. Greubel, Jun 04 2023 *)
  • PARI
    Vec((4-7*x)/((1-2*x)*(1-4*x)) + O(x^30)) \\ Colin Barker, Aug 23 2017
    
  • SageMath
    A291009=BinaryRecurrenceSequence(6,-8,4,17)
    [A291009(n) for n in range(41)] # G. C. Greubel, Jun 04 2023

Formula

a(n) = 6*a(n-1) - 8*a(n-2) for n >= 3.
From Colin Barker, Aug 23 2017: (Start)
G.f.: (4 - 7*x) / ((1 - 2*x)*(1 - 4*x)).
a(n) = 2^(n-1) * (9*2^n - 1).
(End)

A291010 p-INVERT of (1,1,1,1,1,...), where p(S) = (1 - 2*S)*(1 - 3*S).

Original entry on oeis.org

5, 24, 108, 468, 1980, 8244, 33948, 138708, 563580, 2280564, 9200988, 37040148, 148869180, 597602484, 2396787228, 9606280788, 38482518780, 154102262004, 616925608668, 2469252116628, 9881657512380, 39540577187124, 158204150161308, 632942124883668
Offset: 0

Views

Author

Clark Kimberling, Aug 23 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
    [36*(4^(n-1)-3^(n-2)): n in [0..40]]; // G. C. Greubel, Jun 04 2023
    
  • Mathematica
    z = 60; s = x/(1-x); p = (1-2s)(1-3s);
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A000012 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* this sequence *)
    LinearRecurrence[{7,-12}, {5,24}, 40] (* G. C. Greubel, Jun 04 2023 *)
  • PARI
    Vec((5-11*x)/((1-3*x)*(1-4*x)) + O(x^30)) \\ Colin Barker, Aug 23 2017
    
  • SageMath
    A291010=BinaryRecurrenceSequence(7,-12,5,24)
    [A291010(n) for n in range(41)] # G. C. Greubel, Jun 04 2023

Formula

G.f.: (5 - 11*x)/(1 - 7*x + 12*x^2).
a(n) = 7*a(n-1) - 12*a(n-2) for n >= 3.
a(n) = 9*4^n - 4*3^n. - Colin Barker, Aug 23 2017
E.g.f.: 9*exp(4*x) - 4*exp(3*x). - G. C. Greubel, Jun 04 2023

A291011 p-INVERT of (1,1,1,1,1,...), where p(S) = (1 - S)^2 * (1 - 2*S).

Original entry on oeis.org

4, 15, 52, 172, 552, 1736, 5384, 16536, 50440, 153112, 463176, 1397720, 4210568, 12668568, 38083528, 114414424, 343587336, 1031482904, 3095956040, 9291013848, 27879595144, 83652416920, 250985562312, 753015407192, 2259167856392, 6777755227416, 20333785775944
Offset: 0

Views

Author

Clark Kimberling, Aug 23 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
    [8*3^n - 2^(n-1)*(8+n): n in [0..40]]; // G. C. Greubel, Jun 04 2023
    
  • Mathematica
    z = 60; s = x/(1-x); p = (1-s)^2*(1-2*s);
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A000012 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* this sequence *)
    LinearRecurrence[{7,-16,12},{4,15,52},30] (* Harvey P. Dale, Sep 23 2017 *)
  • PARI
    Vec((4 -13*x +11*x^2)/((1-2*x)^2*(1-3*x)) + O(x^30)) \\ Colin Barker, Aug 23 2017
    
  • SageMath
    [8*3^n - 2^(n-1)*(8+n) for n in range(41)] # G. C. Greubel, Jun 04 2023

Formula

G.f.: (4 - 13*x + 11*x^2)/((1-2*x)^2 * (1-3*x)).
a(n) = 7*a(n-1) - 16*a(n-2) + 12*a(n-3) for n >= 4.
a(n) = 8*3^n - 2^(n-1)*(8+n). - Colin Barker, Aug 23 2017
E.g.f.: 8*exp(3*x) - (4 + x)*exp(2*x). - G. C. Greubel, Jun 04 2023
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