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 1-7 of 7 results.

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.

A292480 p-INVERT of the odd positive integers, where p(S) = 1 - S^2.

Original entry on oeis.org

0, 1, 6, 20, 56, 160, 480, 1456, 4384, 13136, 39360, 118064, 354272, 1062928, 3188736, 9565936, 28697632, 86093264, 258280512, 774841520, 2324523104, 6973567888, 20920705152, 62762119792, 188286360736, 564859074896, 1694577214656, 5083731648560
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 = (1,3,5,7,9,...) = A005408, in some cases t(1,3,5,7,9,...) is a shifted (or differently indexed) version of the cited sequence:
p(S) *********** t(1,3,5,7,9,...)
1 - S A003946
1 - S^2 A292480
1 - S^3 (not yet in OEIS)
(1 - S)^2 (not yet in OEIS)
(1 - S)^3 (not yet in OEIS)
1 - S - S^2 A289786
1 + S - S^2 A289484
1 - S - 2 S^2 A289785
1 - S - 3 S^2 A289786
1 - S - 4 S^2 A289787
1 - S - 5 S^2 A289788
1 - S - 6 S^2 A289789
1 - S - 7 S^2 A289790
1 + S - 2 S^2 A289791
1 - S + S^2 - S^3 A289792
1 + S - 3 S^2 A289793
1 - S - S^2 - S^3 A289794

Examples

			s = (1,3,5,7,9,...), S(x) = x + 3 x^2 + 5 x^3 + 7 x^4 + ...,
p(S(x)) = 1 - ( x + 3 x^2 + 5 x^3 + 7 x^4 + ...)^2,
1/p(S(x)) = 1 + x^2 + 6 x^3 + 20 x^4 + 56 x^5 + ...
T(x) = (-1 + 1/p(S(x)))/x = x + 6 x^2 + 20 x^3 + 56 x^4 + ...
t(s) = (0,1,2,20,56,...).
		

Crossrefs

Programs

  • Magma
    I:=[0,1,6,20]; [n le 4 select I[n] else 4*Self(n-1)- 5*Self(n-2)+6*Self(n-3): n in [1..30]]; // Vincenzo Librandi, Oct 03 2017
  • Mathematica
    z = 60; s = x (x + 1)/(1 - x)^2; p = 1 - s^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A005408 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A292480 *)
    Join[{0}, LinearRecurrence[{4, -5, 6}, {1, 6, 20}, 30]] (* Vincenzo Librandi, Oct 03 2017 *)

Formula

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

A292532 p-INVERT of the squares (A000290), where p(S) = 1 - S^3.

Original entry on oeis.org

0, 0, 1, 12, 75, 329, 1158, 3606, 10971, 35601, 126168, 467541, 1722714, 6173070, 21563906, 74452230, 257613930, 899546303, 3166966692, 11185908147, 39459021883, 138761604786, 486746839758, 1705955898935, 5982257083623, 20999661326520, 73772324787965
Offset: 0

Views

Author

Clark Kimberling, Oct 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).
See A292479 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x (x + 1)/(1 - x)^3; p = 1 - s^3;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A005408 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A292532 *)
    LinearRecurrence[{9,-36,85,-123,129,-83,36,-9,1},{0,0,1,12,75,329,1158,3606,10971},30] (* Harvey P. Dale, Sep 27 2023 *)

Formula

G.f.: -((x^2 (1 + x)^3)/((-1 + 4 x - 2 x^2 + x^3) (1 - 5 x + 14 x^2 - 18 x^3 + 18 x^4 - 7 x^5 + x^6))).
a(n) = 9*a(n-1) - 36*a(n-2) + 85*a(n-3) - 123*a(n-4) + 129*a(n-5) - 83*a(n-6) + 36*a(n-7) - 9*a(n-8) + a(n-9) for n >= 10.

A292533 p-INVERT of the squares (A000290), where p(S) = (1 - S)^2.

Original entry on oeis.org

2, 11, 46, 187, 748, 2948, 11480, 44273, 169374, 643601, 2431526, 9140616, 34212350, 127563959, 474022478, 1756118055, 6488228880, 23912815820, 87935847700, 322713694333, 1182114988606, 4322734288413, 15782353895178, 57537481431056, 209479529802682
Offset: 0

Views

Author

Clark Kimberling, Oct 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).
See A292479 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x (x + 1)/(1 - x)^3; p = (1 - s)^2;
    Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A005408 *)
    Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1]  (* A292533 *)

Formula

G.f.: -(((1 + x) (-2 + 7 x - 5 x^2 + 2 x^3))/(-1 + 4 x - 2 x^2 + x^3)^2).
a(n) = 8*a(n-1) - 20*a(n-2) + 18*a(n-3) - 12*a(n-4) + 4*a(n-5) - a(n-6) for n >= 7.

A292534 p-INVERT of the squares (A000290), where p(S) = 1 + S - S^2.

Original entry on oeis.org

-1, -2, 4, 21, 30, 11, 80, 622, 2055, 4584, 10711, 34354, 115480, 341213, 934750, 2640483, 7874188, 23564242, 68738591, 198108496, 575654335, 1688669686, 4951141372, 14443935957, 42064267934, 122731975243, 358682023576, 1047906654118, 3058580566407
Offset: 0

Views

Author

Clark Kimberling, Oct 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).
See A292479 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x (x + 1)/(1 - x)^3; 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]  (* A292534 *)

Formula

G.f.: ((1 + x) (-1 + 4 x - 2 x^2 + x^3))/(1 - 5 x + 12 x^2 - 22 x^3 + 16 x^4 - 7 x^5 + x^6).
a(n) = 5*a(n-1) - 12*a(n-2) + 22*a(n-3) - 16*a(n-4) + 7*a(n-5) - a(n-6) for n >= 7.

A292535 p-INVERT of the squares (A000290), where p(S) = 1 + S - 2 S^2.

Original entry on oeis.org

1, 7, 38, 189, 909, 4368, 21093, 102051, 493702, 2387689, 11546425, 55837024, 270025769, 1305841103, 6315023830, 30539305893, 147687325509, 714212301776, 3453913488845, 16703042620715, 80775512179990, 390628431683601, 1889069687788593, 9135495517900480
Offset: 0

Views

Author

Clark Kimberling, Oct 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).
See A292479 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x (x + 1)/(1 - x)^3; 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]  (* A292535 *)

Formula

G.f.: -(((1 + x) (-1 + x - 5 x^2 + x^3))/((-1 + 2 x - 4 x^2 + x^3) (-1 + 5 x - x^2 + x^3))).
a(n) = 7*a(n-1) - 15*a(n-2) + 24*a(n-3) - 11*a(n-4) + 5*a(n-5) - a(n-6) for n >= 7.

A292536 p-INVERT of the squares (A000290), where p(S) = 1 + S - 3 S^2.

Original entry on oeis.org

1, 8, 48, 255, 1310, 6773, 35260, 183740, 956765, 4980320, 25924725, 134956612, 702554244, 3657326875, 19039098206, 99112598721, 515954630808, 2685927132776, 13982245762937, 72787973059648, 378915453775913, 1972536332660240, 10268516498713448
Offset: 0

Views

Author

Clark Kimberling, Oct 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).
See A292479 for a guide to related sequences.

Crossrefs

Programs

  • Mathematica
    z = 60; s = x (x + 1)/(1 - x)^3; 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]  (* A292536 *)

Formula

G.f.: -(((1 + x) (-1 - 6 x^2 + x^3))/(1 - 7 x + 14 x^2 - 26 x^3 + 10 x^4 - 5 x^5 + x^6)).
a(n) = 7*a(n-1) - 14*a(n-2) + 26*a(n-3) - 10*a(n-4) + 5*a(n-5) - a(n-6) for n >= 7.
Showing 1-7 of 7 results.