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.

Showing 1-10 of 16 results. Next

A291382 p-INVERT of (1,1,0,0,0,0,...), where p(S) = 1 - 2 S - S^2.

Original entry on oeis.org

2, 7, 22, 70, 222, 705, 2238, 7105, 22556, 71608, 227332, 721705, 2291178, 7273743, 23091762, 73308814, 232731578, 738846865, 2345597854, 7446508273, 23640235416, 75050038224, 238259397096, 756395887969, 2401310279090, 7623377054503, 24201736119310
Offset: 0

Views

Author

Clark Kimberling, Sep 04 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).
In the following guide to p-INVERT sequences using s = (1,1,0,0,0,...) = A019590, in some cases t(1,1,0,0,0,...) is a shifted version of the cited sequence:
p(S) t(1,1,0,0,0,...)
1 - S A000045 (Fibonacci numbers)
1 - S^2 A094686
1 - S^3 A115055
1 - S^4 A291379
1 - S^5 A281380
1 - S^6 A281381
1 - 2 S A002605
1 - 3 S A125145
(1 - S)^2 A001629
(1 - S)^3 A001628
(1 - S)^4 A001629
(1 - S)^5 A001873
(1 - S)^6 A001874
1 - S - S^2 A123392
1 - 2 S - S^2 A291382
1 - S - 2 S^2 A124861
1 - 2 S - S^2 A291383
(1 - 2 S)^2 A073388
(1 - 3 S)^2 A291387
(1 - 5 S)^2 A291389
(1 - 6 S)^2 A291391
(1 - S)(1 - 2 S) A291393
(1 - S)(1 - 3 S) A291394
(1 - 2 S)(1 - 3 S) A291395
(1 - S)(1 - 2 S) A291393
(1 - S)(1 - 2 S)(1 - 3 S) A291396
1 - S - S^3 A291397
1 - S^2 - S^3 A291398
1 - S - S^2 - S^3 A186812
1 - S - S^2 - S^3 - S^4 A291399
1 - S^2 - S^4 A291400
1 - S - S^4 A291401
1 - S^3 - S^4 A291402
1 - 2 S^2 - S^4 A291403
1 - S^2 - 2 S^4 A291404
1 - 2 S^2 - 2 S^4 A291405
1 - S^3 - S^6 A291407
(1 - S)(1 - S^2) A291408
(1 - S^2)(1 - S)^2 A291409
1 - S - S^2 - 2 S^3 A291410
1 - 2 S - S^2 + S^3 A291411
1 - S - 2 S^2 + S^3 A291412
1 - 3 S + S^2 + S^3 A291413
1 - 2 S + S^3 A291414
1 - 3 S + S^2 A291415
1 - 4 S + S^2 A291416
1 - 4 S + 2 S^2 A291417

Crossrefs

Programs

  • Mathematica
    z = 60; s = x + x^2; p = 1 - 2 s - s^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A019590 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291382 *)

Formula

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

A292479 p-INVERT of the positive squares, where p(S) = 1 - S^2.

Original entry on oeis.org

0, 1, 8, 35, 120, 392, 1336, 4725, 16792, 59191, 207536, 727440, 2553264, 8968569, 31502248, 110627195, 388451624, 1364010648, 4789766120, 16819647565, 59063332152, 207403715119, 728306773600, 2557481457440, 8980717116000, 31536219644721, 110740934436168
Offset: 0

Views

Author

Clark Kimberling, Oct 02 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).
In the following guide to p-INVERT sequences using s = (1,4,9,16,...) = A000290, in some cases t(1,4,9,16,...) is a shifted (or differently indexed) version of the cited sequence:
** p(S) ********** t(1, 4, 9, 16,...)
1 - S A033453
1 - S^2 A292479
1 - S^3 (not yet in OEIS)
(1 - S)^2 (not yet in OEIS)
1 - S - S^2 A289779
1 + S - S^2 (not yet in OEIS)
1 + S - 2 S^2 (not yet in OEIS)
1 + S - 3 S^2 (not yet in OEIS)

Examples

			s = (1,4,9,16,25,...), S(x) = x + 4 x^2 + 9 x^3 + 16 x^4 + ...,
p(S(x)) = 1 - (x + 4 x^2 + 9 x^3 + 16 x^4 + ...)^2,
1/p(S(x)) = 1 + x^2 + 8*x^3 + 35*x^4 + 120*x^5 + ...
T(x) = (-1 + 1/p(S(x)))/x = x + 8 x^2 + 35 x^3 + 120 x^4 + ...
t(s) = (0, 1, 8, 35, 120, ...).
		

Crossrefs

Programs

  • Magma
    I:=[0,1,8,35,120,392]; [n le 6 select I[n] else 6*Self(n-1)-14*Self(n-2)+22*Self(n-3)-14*Self(n-4)+6*Self(n-5)- Self(n-6): n in [1..30]]; // Vincenzo Librandi, Oct 03 2017
  • Mathematica
    z = 60; s = x (x + 1)/(1 - x)^3; p = 1 - s^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A000290 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A292479 *)
    LinearRecurrence[{6, -14, 22, -14, 6, -1}, {0, 1, 8, 35, 120, 392}, 30] (* Vincenzo Librandi, Oct 03 2017 *)

Formula

G.f.: x*(1 + x)^2/((-1 + 2*x - 4*x^2 + x^3)*(-1 + 4*x - 2*x^2 + x^3)).
a(n) = 6*a(n-1) - 14*a(n-2) + 22*a(n-3) - 14*a(n-4) + 6*a(n-5) - a(n-6) for n >= 7.

A292481 p-INVERT of the odd positive integers, where p(S) = 1 - S^3.

Original entry on oeis.org

0, 0, 1, 9, 42, 139, 381, 984, 2685, 8061, 25434, 79695, 242577, 721584, 2131785, 6333633, 18984618, 57194883, 172319157, 517851144, 1552599333, 4651054101, 13939132698, 41810229351, 125475990057, 376585031520, 1129975049169, 3389800055481, 10168040440746
Offset: 0

Views

Author

Clark Kimberling, Oct 02 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 A292480 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x (x + 1)/(1 - x)^2; p = 1 - s^3;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A005408 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A292481 *)
    LinearRecurrence[{6,-15,21,-12,9},{0,0,1,9,42,139},30] (* Harvey P. Dale, Jun 06 2024 *)

Formula

G.f.: -((x^2 (1 + x)^3)/((-1 + 3 x) (1 - 3 x + 6 x^2 - 3 x^3 + 3 x^4))).
a(n) = 6*a(n-1) - 25*a(n-2) + 21*a(n-3) - 12*a(n-4) + 9*a(n-5) for n >= 6.

A292482 p-INVERT of the odd positive integers, where p(S) = (1 - S)^2.

Original entry on oeis.org

2, 9, 32, 112, 384, 1296, 4320, 14256, 46656, 151632, 489888, 1574640, 5038848, 16061328, 51018336, 161558064, 510183360, 1607077584, 5050815264, 15841193328, 49589822592, 154968195600, 483500770272, 1506290861232, 4686238234944, 14560811658576
Offset: 0

Views

Author

Clark Kimberling, Oct 02 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 A292480 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x (x + 1)/(1 - x)^2; p = 1 - s^3;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A005408 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A292482 *)

Formula

G.f.: ((1 + x) (2 - 5 x + x^2))/(-1 + 3 x)^2.
a(n) = 6*a(n-1) - 9*a(n-2) for n >= 3.
a(n) = 16*3^(n-3)*(4 + n) for n>1. - Colin Barker, Oct 03 2017

A292483 p-INVERT of the odd positive integers, where p(S) = (1 - S)^3.

Original entry on oeis.org

3, 15, 61, 240, 912, 3376, 12240, 43632, 153360, 532656, 1831248, 6240240, 21100176, 70858800, 236510928, 785115504, 2593432080, 8528565168, 27932538960, 91144257264, 296391022992, 960802812720, 3105562639824, 10010945435760, 32189993590032, 103264606820016
Offset: 0

Views

Author

Clark Kimberling, Oct 02 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 A292480 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x (x + 1)/(1 - x)^2; p = (1 - s)^3;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A005408 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A292483 *)

Formula

G.f.: -(((1 + x) (3 - 15 x + 22 x^2 - 7 x^3 + x^4))/(-1 + 3 x)^3).
a(n) = 9*a(n-1) - 27*a(n-2) + 27*a(n-3) for n >= 6.
a(n) = 16*3^(n-5)*(51 + 22*n + 2*n^2) for n>2. - Colin Barker, Oct 03 2017

A292484 p-INVERT of the odd positive integers, where p(S) = 1 + S - S^2.

Original entry on oeis.org

-1, -1, 4, 9, 5, 8, 63, 183, 348, 745, 2061, 5456, 12991, 30831, 76660, 192137, 472597, 1155032, 2843007, 7024935, 17315404, 42592489, 104847389, 258355104, 636507775, 1567442143, 3859933668, 9507231753, 23417547813, 57675809960, 142047927231, 349856144791
Offset: 0

Views

Author

Clark Kimberling, Oct 02 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 A292480 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x (x + 1)/(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]  (* A292484 *)
    LinearRecurrence[{3,-4,7,-1},{-1,-1,4,9},40] (* Harvey P. Dale, Sep 22 2024 *)

Formula

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

A292485 p-INVERT of the odd positive integers, where p(S) = 1 - S - 2 S^2.

Original entry on oeis.org

1, 6, 28, 120, 504, 2128, 9016, 38208, 161864, 685648, 2904408, 12303264, 52117544, 220773552, 935211704, 3961620096, 16781691912, 71088388112, 301135245080, 1275629368416, 5403652717288, 22890240236144, 96964613663352, 410748694893888, 1739959393240264
Offset: 0

Views

Author

Clark Kimberling, Oct 02 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 A292480 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x (x + 1)/(1 - x)^2; p = 1 - s - 2 s^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A005408 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A292485 *)
    LinearRecurrence[{5,-5,7,2},{1,6,28,120},30] (* Harvey P. Dale, Oct 14 2023 *)

Formula

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

A292486 p-INVERT of the odd positive integers, where p(S) = 1 - S - 3 S^2.

Original entry on oeis.org

1, 7, 36, 165, 747, 3420, 15705, 72063, 330516, 1515933, 6953283, 31893516, 146289393, 671000247, 3077745156, 14117009877, 64751939163, 297004363452, 1362300384969, 6248602953135, 28661108314356, 131462846314317, 602994126047283, 2765815028667756
Offset: 0

Views

Author

Clark Kimberling, Oct 03 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 A292480 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x (x + 1)/(1 - x)^2; p = 1 - s - 3 s^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A005408 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A292486 *)
    LinearRecurrence[{5,-4,9,3},{1,7,36,165},30] (* Harvey P. Dale, Sep 29 2024 *)
  • PARI
    x='x+O('x^99); Vec(((1+x)*(1+x+4*x^2))/(1-5*x+4*x^2-9*x^3-3*x^4)) \\ Altug Alkan, Oct 03 2017

Formula

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

A292487 p-INVERT of the odd positive integers, where p(S) = 1 - S - 4 S^2.

Original entry on oeis.org

1, 8, 44, 212, 1020, 4980, 24348, 118868, 580156, 2831924, 13824092, 67481876, 329408892, 1607991540, 7849328028, 38316090836, 187038012604, 913016364980, 4456842098396, 21755843899028, 106200025265148, 518409923170932, 2530591191342108, 12352949840710484
Offset: 0

Views

Author

Clark Kimberling, Oct 03 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 A292480 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x (x + 1)/(1 - x)^2; p = 1 - s - 4 s^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A005408 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A292487 *)
  • PARI
    x='x+O('x^99); Vec(((1+x)*(1+2*x+5*x^2))/(1-5*x+3*x^2-11*x^3-4*x^4)) \\ Altug Alkan, Oct 03 2017

Formula

G.f.: -(((1 + x) (1 + 2 x + 5 x^2))/(-1 + 5 x - 3 x^2 + 11 x^3 + 4 x^4)).
a(n) = 5*a(n-1) - 3*a(n-2) + 11*a(n-3) + 4*a(n-4) for n >= 5.

A292488 p-INVERT of the odd positive integers, where p(S) = 1 - S - 5 S^2.

Original entry on oeis.org

1, 9, 52, 261, 1323, 6814, 35077, 180261, 926348, 4761289, 24472527, 125783886, 646502873, 3322895889, 17079026852, 87782799261, 451186103523, 2319006747614, 11919233055677, 61262485125261, 314876977751548, 1618404981969089, 8318279426249127
Offset: 0

Views

Author

Clark Kimberling, Oct 03 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 A292480 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x (x + 1)/(1 - x)^2; p = 1 - s - 5 s^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A005408 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A292488 *)
    LinearRecurrence[{5,-2,13,5},{1,9,52,261},30] (* Harvey P. Dale, Jul 31 2025 *)
  • PARI
    x='x+O('x^99); Vec(((1+x)*(1+3*x+6*x^2))/(1-5*x+2*x^2-13*x^3-5*x^4)) \\ Altug Alkan, Oct 03 2017

Formula

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