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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A291012 p-INVERT of (1,1,1,1,1,...), where p(S) = (1 - S^2)*(1 - 2*S).

Original entry on oeis.org

2, 7, 22, 68, 208, 632, 1912, 5768, 17368, 52232, 156952, 471368, 1415128, 4247432, 12746392, 38247368, 114758488, 344308232, 1032990232, 3099101768, 9297567448, 27893226632, 83680728472, 251044282568, 753137042008, 2259419514632, 6778275321112
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] cat [8*3^(n-1) - 2^(n-1): n in [1..40]]; // G. C. Greubel, Jun 04 2023
    
  • Mathematica
    z = 60; s = x/(1-x); p = (1-s)^2(1-2s);
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A000012 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* this sequence *)
    LinearRecurrence[{5,-6}, {2,7,22}, 40] (* G. C. Greubel, Jun 04 2023 *)
  • PARI
    Vec((2 -3*x -x^2)/((1-2*x)*(1-3*x)) + O(x^30)) \\ Colin Barker, Aug 23 2017
    
  • SageMath
    [8*3^(n-1) - 2^(n-1) - int(n==0)/6 for n in range(41)] # G. C. Greubel, Jun 04 2023

Formula

G.f.: (2 - 3 x - x^2)/(1 - 5*x + 6*x^2).
a(n) = 5*a(n-1) - 6*a(n-2) for n >= 4.
a(n) = (16*3^n - 3*2^n) / 6 for n > 0. - Colin Barker, Aug 23 2017
E.g.f.: (1/6)*(-1 - 3*exp(2*x) + 16*exp(3*x)). - G. C. Greubel, Jun 04 2023

A291024 p-INVERT of (1,1,1,1,1,...), where p(S) = (1 - 2 S^2)^2.

Original entry on oeis.org

0, 4, 8, 24, 64, 172, 456, 1200, 3136, 8148, 21064, 54216, 139008, 355196, 904840, 2298720, 5825408, 14729636, 37168008, 93612408, 235369664, 590852172, 1481051720, 3707411472, 9268764096, 23145174388, 57732471752, 143857070376, 358113876352, 890666303260
Offset: 0

Views

Author

Clark Kimberling, Aug 24 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

  • Mathematica
    z = 60; s = x/(1 - x); p = 1 - 3 s^2 + 2 s^3;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A000012 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A291024 *)
    u/4 (* A291142 *)
  • PARI
    concat(0, Vec(4*x*(1 - 2*x) / (1 - 2*x - x^2)^2 + O(x^30))) \\ Colin Barker, Aug 24 2017

Formula

G.f.: -((4 (-x + 2 x^2))/(-1 + 2 x + x^2)^2).
a(n) = 4*a(n-1) - 2 a(n-2) - 4*a(n-3) - a(n-4) for n >= 5.
a(n) = 4*A291142(n) for n >= 0.
a(n) = ((1+sqrt(2))^n*(3*sqrt(2) + 2*(-1+sqrt(2))*n) - (1-sqrt(2))^n*(3*sqrt(2) + 2*(1+sqrt(2))*n)) / 4. - Colin Barker, Aug 24 2017
E.g.f.: exp(x)*x*cosh(sqrt(2)*x) + 3*exp(x)*sinh(sqrt(2)*x)/sqrt(2). - Stefano Spezia, Jun 07 2025

A289782 p-INVERT of the Lucas numbers (A000032), where p(S) = 1 - S - S^2.

Original entry on oeis.org

2, 9, 35, 146, 593, 2428, 9911, 40495, 165399, 675637, 2759792, 11273144, 46048100, 188095781, 768327108, 3138436438, 12819777601, 52365789305, 213901984464, 873739509697, 3569021260182, 14578615958179, 59550231769665, 243248749683441, 993614171826023
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 = (2 - x) x/(1 - x - x^2); p = 1 - s - s^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A000032 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1] (* A289782 *)

Formula

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

A289783 p-INVERT of the (3^n), where p(S) = 1 - S - S^2.

Original entry on oeis.org

1, 5, 24, 113, 527, 2446, 11325, 52369, 242008, 1117997, 5163891, 23849270, 110142089, 508652653, 2349005592, 10847859961, 50095958215, 231345247934, 1068361195173, 4933730638937, 22784141325656, 105217952251285, 485900111176779, 2243903303473318
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).

Crossrefs

Programs

  • Mathematica
    z = 60; s = x/(1 - 3*x); p = 1 - s - s^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A000244 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1] (* A289783 *)
  • PARI
    Vec(x*(1 - 2*x) / (1 - 7*x + 11*x^2) + O(x^30)) \\ Colin Barker, Aug 11 2017

Formula

G.f.: (1 - 2 x)/(1 - 7 x + 11 x^2).
a(n) = 7*a(n-1) - 11*a(n-2).
a(n) = (2^(-n-1)*((7-sqrt(5))^(n+1)*(-4+sqrt(5)) + (4+sqrt(5))*(7+sqrt(5))^(n+1))) / (11*sqrt(5)). - Colin Barker, Aug 11 2017
a(n) = A099453(n) - 2*A099453(n-1). - R. J. Mathar, Jul 08 2022
E.g.f.: exp(7*x/2)*(5*cosh(sqrt(5)*x/2) + 3*sqrt(5)*sinh(sqrt(5)*x/2))/5. - Stefano Spezia, Aug 05 2025

A289784 p-INVERT of the (4^n), where p(S) = 1 - S - S^2.

Original entry on oeis.org

1, 6, 35, 201, 1144, 6477, 36557, 205950, 1158967, 6517653, 36638504, 205911129, 1157068585, 6501305814, 36527449211, 205222232433, 1152978556888, 6477584595765, 36391668781013, 204450911709582, 1148616498546991, 6452981164440861, 36253117007574920
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).

Crossrefs

Programs

  • Mathematica
    z = 60; s = x/(1 - 4*x); p = 1 - s - s^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A000302 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1] (* A289784 *)
  • PARI
    Vec(x*(1 - 3*x) / (1 - 9*x + 19*x^2) + O(x^30)) \\ Colin Barker, Aug 11 2017

Formula

G.f.: (1 - 3 x)/(1 - 9 x + 19 x^2).
a(n) = 9*a(n-1) - 19*a(n-2).
a(n) = (2^(-2-n)*((9-sqrt(5))^(n+1)*(-11+3*sqrt(5)) + (9+sqrt(5))^(n+1)*(11+3*sqrt(5)))) / (19*sqrt(5)). - Colin Barker, Aug 11 2017
a(n) = A081574(n+1)-3*A081574(n). - R. J. Mathar, Jul 08 2022

A289796 a(n) = (1/3)*A289795(n).

Original entry on oeis.org

1, 8, 54, 361, 2420, 16227, 108802, 729512, 4891347, 32796280, 219897701, 1474404984, 9885824398, 66284043461, 444431768220, 2979896612959, 19980083465882, 133965632756376, 898234023419479, 6022621953315440, 40381430948778393, 270755823312682408
Offset: 0

Views

Author

Clark Kimberling, Aug 12 2017

Keywords

Comments

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.: (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).

A289797 p-INVERT of the triangular numbers (A000217), where p(S) = 1 - S - S^2.

Original entry on oeis.org

1, 5, 21, 84, 330, 1291, 5052, 19784, 77500, 303608, 1189372, 4659245, 18252027, 71500068, 280092848, 1097230105, 4298267549, 16837948391, 65960645632, 258392925744, 1012223324455, 3965263584006, 15533444957104, 60850409347588, 238374187312038
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/(1 - x)^3; p = 1 - s - s^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A000217 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1] (* A289797 *)
    LinearRecurrence[{7,-17,23,-16,6,-1},{1,5,21,84,330,1291},30] (* Harvey P. Dale, Jul 10 2020 *)

Formula

G.f.: (1 - 2 x + 3 x^2 - x^3)/(1 - 7 x + 17 x^2 - 23 x^3 + 16 x^4 - 6 x^5 + x^6).
a(n) = 7*a(n-1) - 17*a(n-2) + 23*a(n-3) - 16*a(n-4) + 6*a(n-5) - a(n-6).

A289798 p-INVERT of (-1 + 2^n), where p(S) = 1 - S - S^2.

Original entry on oeis.org

1, 5, 22, 93, 387, 1602, 6623, 27377, 113174, 467877, 1934315, 7996978, 33061703, 136686153, 565097958, 2336269341, 9658775347, 39932014114, 165089847535, 682526498529, 2821750872886, 11665888441301, 48229967585083, 199395852702354, 824356889826903
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/((1 - 2*x)*(1 - x)); p = 1 - s - s^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A000225 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1] (* A289798 *)

Formula

G.f.: (1 - 2 x + 2 x^2)/(1 - 7 x + 15 x^2 - 14 x^3 + 4 x^4).
a(n) = 7*a(n-1) - 15*a(n-2) + 14*a(n-3) - 4*a(n-4).

A289799 p-INVERT of (n^3), where p(S) = 1 - S - S^2.

Original entry on oeis.org

1, 10, 62, 377, 2232, 13015, 75898, 444014, 2601503, 15244128, 89303905, 523084546, 3063814838, 17945741321, 105115487400, 615706236199, 3606449444722, 21124456768934, 123734572586495, 724763983514112, 4245239506761217, 24866107799273146, 145650985218990062
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*(1 + 4*x + x^2)/(1 - x)^4; p = 1 - s - s^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A000578 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1] (* A289799 *)
    LinearRecurrence[{9,-27,55,-36,55,-27,9,-1},{1,10,62,377,2232,13015,75898,444014},30] (* Harvey P. Dale, Jan 07 2024 *)

Formula

G.f.: (1 + x - x^2 + 34 x^3 - x^4 + x^5 + x^6)/(1 - 9 x + 27 x^2 - 55 x^3 + 36 x^4 - 55 x^5 + 27 x^6 - 9 x^7 + x^8).
a(n) = 9*a(n-1) - 27*a(n-2) + 55*a(n-3) - 36*a(n-4) + 55*a(n-5) - 27*a(n-6) + 9*a(n-7) - a(n-8).

A289800 p-INVERT of the central binomial coefficients (A000984), where p(S) = 1 - S - S^2.

Original entry on oeis.org

1, 4, 17, 75, 336, 1517, 6879, 31276, 142439, 649431, 2963266, 13528285, 61785007, 282257992, 1289734455, 5894167695, 26939918564, 123142940445, 562928407213, 2573477722376, 11765383864555, 53790586563231, 245933621620228, 1124446028551665, 5141224466008849
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/Sqrt[1 - 4 x]; p = 1 - s - s^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1]  (* A000984 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1] (* A289800 *)
Previous Showing 31-40 of 81 results. Next