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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A176537 Decimal expansion of 5 + sqrt(26).

Original entry on oeis.org

1, 0, 0, 9, 9, 0, 1, 9, 5, 1, 3, 5, 9, 2, 7, 8, 4, 8, 3, 0, 0, 2, 8, 2, 2, 4, 1, 0, 9, 0, 2, 2, 7, 8, 1, 9, 8, 9, 5, 6, 3, 7, 7, 0, 9, 4, 6, 0, 9, 9, 5, 9, 6, 4, 0, 7, 5, 8, 4, 9, 7, 0, 8, 0, 4, 4, 2, 5, 9, 3, 3, 6, 3, 2, 0, 6, 2, 2, 2, 4, 1, 9, 5, 5, 8, 8, 3, 4, 8, 8, 5, 1, 0, 9, 3, 9, 3, 2, 0, 0, 8, 3, 6, 1, 1
Offset: 2

Views

Author

Klaus Brockhaus, Apr 24 2010

Keywords

Comments

Continued fraction expansion of 5 + sqrt(26) is A010692.
This is the shape of a 10-extension rectangle; see A188640 for definitions. - Clark Kimberling, Apr 09 2011

Examples

			5+sqrt(26) = 10.09901951359278483002...
		

Crossrefs

Cf. A010481 (decimal expansion of sqrt(26)), A010692 (all 10's sequence).

Programs

  • Mathematica
    r=10; t = (r + (4+r^2)^(1/2))/2; FullSimplify[t]
    N[t, 130]
    RealDigits[N[t, 130]][[1]]
    RealDigits[5+Sqrt[26],10,120][[1]] (* Harvey P. Dale, Jun 24 2013 *)
  • PARI
    5+sqrt(26) \\ Michel Marcus, Jul 23 2018

Formula

a(n) = A010481(n-2) for n > 3.
Equals exp(arcsinh(5)), since arcsinh(x) = log(x + sqrt(x^2 + 1)). - Stanislav Sykora, Nov 01 2013
Equals limit_{n->infinity} S(n, 2*sqrt(2*13))/ S(n-1, 2*sqrt(2*13)), with the S-Chebyshev polynomilas (see A049310). - Wolfdieter Lang, Nov 15 2023

A188659 Decimal expansion of (1+sqrt(26))/5.

Original entry on oeis.org

1, 2, 1, 9, 8, 0, 3, 9, 0, 2, 7, 1, 8, 5, 5, 6, 9, 6, 6, 0, 0, 5, 6, 4, 4, 8, 2, 1, 8, 0, 4, 5, 5, 6, 3, 9, 7, 9, 1, 2, 7, 5, 4, 1, 8, 9, 2, 1, 9, 9, 1, 9, 2, 8, 1, 5, 1, 6, 9, 9, 4, 1, 6, 0, 8, 8, 5, 1, 8, 6, 7, 2, 6, 4, 1, 2, 4, 4, 4, 8, 3, 9, 1, 1, 7, 6, 6, 9, 7, 7, 0, 2, 1, 8, 7, 8, 6, 4, 0, 1, 6, 7, 2, 2, 3, 8, 0, 5, 1, 6, 4, 8, 2, 0, 7, 9, 8, 2, 1, 3, 2, 2, 8, 6, 3, 5, 5, 8, 6, 8
Offset: 1

Views

Author

Clark Kimberling, Apr 09 2011

Keywords

Comments

Decimal expansion of the shape of a (2/5)-extension rectangle; see A188640 for definitions of shape and r-extension rectangle. Briefly, shape=length/width, and an r-extension rectangle is composed of two rectangles of shape 1/r when r<1.
The continued fraction of the constant is 1, 4, 1, 1, 4, 1, ... = A146325.

Examples

			1.219803902718556966005644821804556397912754189219919281516994...
		

Crossrefs

Programs

  • Mathematica
    RealDigits[(1 + Sqrt[26])/5, 10, 111][[1]] (* Robert G. Wilson v, Aug 18 2011 *)

Formula

Equals exp(arcsinh(1/5)). - Amiram Eldar, Jul 04 2023

A188726 Continued fraction of the shape of a (2*Pi)-extension rectangle; shape = Pi + sqrt(1 + Pi^2).

Original entry on oeis.org

6, 2, 3, 1, 1, 3, 2, 1, 16, 47, 1, 4, 2, 7, 1, 5, 317, 4, 1, 1, 1, 2, 13, 1, 38, 37, 1, 4, 1, 13, 1, 59, 3, 17, 1, 2, 2, 2, 5, 1, 3, 1, 3, 9, 1, 3, 4, 1, 2, 2, 1, 1, 2, 1, 23, 8, 9, 84, 1, 3, 1, 2, 1, 1, 3, 5, 5, 1, 1, 16, 1, 8, 4, 11, 1, 3, 1, 16, 4, 1, 1, 1, 1, 18, 1, 12, 1, 21, 3, 3, 1, 2, 4, 2, 10, 3, 5, 6, 1, 1, 25, 4, 10, 1, 5, 2, 1, 4, 16, 2, 5, 4, 2, 1, 4, 1, 1, 2, 1, 1
Offset: 0

Views

Author

Clark Kimberling, Apr 09 2011

Keywords

Comments

See A188640 for definitions of shape and r-extension rectangle. Briefly, an r-extension rectangle is composed of two rectangles of shape r.
A 2*Pi-extension rectangle matches the continued fraction [6,2,3,1,1,3,2,1,16,47,...] of the shape L/W = Pi + sqrt(1 + Pi^2). This is analogous to the matching of a golden rectangle to the continued fraction [1,1,1,1,1,1,1,...]. Specifically, for the (2*Pi)-extension rectangle, 6 squares are removed first, then 2 squares, then 3 squares, then 1 square, then 1 square, ..., so that the original rectangle is partitioned into an infinite collection of squares.

Examples

			6.4385009630654083972232325635946917292621665408132...
		

Crossrefs

Cf. A188640, A188725 (decimal expansion).

Programs

  • Magma
    SetDefaultRealField(RealField(100)); R:= RealField(); ContinuedFraction(Pi(R) + Sqrt(1 + Pi(R)^2)); // G. C. Greubel, Oct 31 2018
  • Maple
    with(numtheory): cfrac(Pi+sqrt(1+Pi^2),120,'quotients'); # Muniru A Asiru, Nov 22 2018
  • Mathematica
    r = 2*Pi; t = (r + (4 + r^2)^(1/2))/2; FullSimplify[t]
    N[t, 130]
    RealDigits[N[t, 130]][[1]] (* A188725 *)
    ContinuedFraction[t, 120] (* A188726 *)
    ContinuedFraction[Pi + Sqrt[1 + Pi^2], 100] (* G. C. Greubel, Oct 31 2018 *)
  • PARI
    default(realprecision, 100); contfrac(Pi + sqrt(1 + Pi^2)) \\ G. C. Greubel, Oct 31 2018
    

A089078 Continued fraction for sqrt(2) + sqrt(3).

Original entry on oeis.org

3, 6, 1, 5, 7, 1, 1, 4, 1, 38, 43, 1, 3, 2, 1, 1, 1, 1, 2, 4, 1, 4, 5, 1, 5, 1, 7, 22, 2, 5, 1, 1, 2, 1, 1, 31, 2, 1, 1, 3, 1, 44, 1, 89, 1, 8, 5, 2, 5, 1, 1, 4, 2, 8, 1, 17, 1, 4, 3, 4, 3, 2, 1, 1, 4, 2, 1, 9, 1, 15, 13, 1, 39, 20, 2, 152, 3, 2, 4, 1, 30, 1, 3, 1, 2, 1, 2, 16, 3, 24, 1, 9, 1, 172, 3, 1, 1
Offset: 0

Views

Author

Jeppe Stig Nielsen, Dec 04 2003

Keywords

Comments

This is the most natural example of the fact that the sum of two periodic continued fractions need not have a periodic continued fraction.
a(n) is the numbers of squares removed at stage n of the continued-fraction partitioning of a rectangle of length L and width W satisfying W=L*sqrt(8); see A188640. - Clark Kimberling, Apr 13 2011

Crossrefs

Cf. A135611.

Programs

  • Mathematica
    r = 8^(1/2); t = (r + (4 + r^2)^(1/2))/2; FullSimplify[t]
    N[t, 130]
    RealDigits[N[t, 130]][[1]]
    ContinuedFraction[t, 120]
    ContinuedFraction[Sqrt[2]+Sqrt[3],100] (* Harvey P. Dale, Aug 17 2019 *)
  • PARI
    contfrac(sqrt(2)+sqrt(3)) \\ Michel Marcus, Mar 12 2017

A188658 Decimal expansion of (1+sqrt(101))/10.

Original entry on oeis.org

1, 1, 0, 4, 9, 8, 7, 5, 6, 2, 1, 1, 2, 0, 8, 9, 0, 2, 7, 0, 2, 1, 9, 2, 6, 4, 9, 1, 2, 7, 5, 9, 5, 7, 6, 1, 8, 6, 9, 4, 5, 0, 2, 3, 4, 7, 0, 0, 2, 6, 3, 7, 7, 2, 9, 0, 5, 7, 2, 8, 2, 8, 2, 9, 7, 3, 2, 8, 4, 9, 1, 2, 3, 1, 5, 5, 1, 9, 7, 0, 3, 8, 1, 2, 3, 6, 1, 7, 7, 6, 9, 2, 4, 5, 3, 9, 5, 2, 3, 5, 2, 3, 6, 6, 2, 9, 9, 5, 0, 3, 2, 6, 5, 2, 6, 1, 3, 2, 3, 1, 8, 8, 1, 5, 9, 3, 5, 8, 5, 7
Offset: 1

Views

Author

Clark Kimberling, Apr 10 2011

Keywords

Comments

Decimal expansion of the shape of a (1/5)-extension rectangle; see A188640 for definitions of shape and r-extension rectangle. Briefly, shape=length/width, and an r-extension rectangle is composed of two rectangles of shape 1/r when r<1.
The continued fraction is 1, 9, 1, 1, 9, 1, 1, 9, 1, 1, 9, 1, 1, 9, 1...

Examples

			1.104987562112089027021926491275957618694502347002...
		

Crossrefs

Cf. A188640.

Programs

  • Mathematica
    r = 1/5; t = (r + (4 + r^2)^(1/2))/2; FullSimplify[t]
    N[t, 130]
    RealDigits[N[t, 130]][[1]]
    ContinuedFraction[t, 120]
    RealDigits[(1+Sqrt[101])/10,10,150][[1]] (* Harvey P. Dale, Nov 29 2020 *)

Formula

Equals exp(arcsinh(1/10)). - Amiram Eldar, Jul 04 2023

Extensions

a(130) corrected by Georg Fischer, Apr 02 2020

A188720 Decimal expansion of (e+sqrt(4+e^2))/2.

Original entry on oeis.org

3, 0, 4, 6, 5, 2, 4, 6, 9, 5, 3, 3, 3, 4, 7, 2, 4, 7, 1, 8, 1, 1, 4, 0, 1, 7, 6, 6, 5, 8, 7, 1, 5, 5, 2, 4, 3, 2, 7, 4, 6, 0, 7, 0, 5, 8, 8, 7, 9, 7, 9, 4, 7, 7, 4, 5, 7, 7, 4, 2, 2, 4, 9, 6, 3, 1, 2, 0, 4, 6, 2, 8, 7, 4, 0, 0, 0, 6, 5, 6, 0, 6, 0, 1, 8, 9, 8, 5, 5, 3, 5, 0, 7, 3, 6, 5, 9, 4, 2, 6, 8, 0, 6, 1, 2, 7, 1, 1, 0, 2, 5, 2, 3, 4, 2, 9, 9, 9, 8, 0, 8, 1, 3, 2, 0, 9, 6, 8, 1, 5
Offset: 1

Views

Author

Clark Kimberling, Apr 09 2011

Keywords

Comments

Decimal expansion of shape of an e-extension rectangle; see A188640 for definitions of shape and r-extension rectangle. Briefly, an r-extension rectangle is composed of two rectangles having shape r.
An e-extension rectangle matches the continued fraction A188721 of the shape L/W = (1/2) *(e+sqrt(4+e^2)). This is analogous to the matching of a golden rectangle to the continued fraction [1,1,1,1,1,1,1,...]. Specifically, for an e-extension rectangle, 3 squares are removed first, then 21 squares, then 2 squares, then 40 squares, then 1 square,..., so that the original rectangle is partitioned into an infinite collection of squares.
(e+sqrt(4+e^2))/2 = [e,e,e,... ] (continued fraction). - Clark Kimberling, Sep 23 2013

Examples

			3.046524695333472471811401766587155243274607058879794774577422496312...
		

Crossrefs

Programs

  • Magma
    SetDefaultRealField(RealField(100)); (Exp(1) +Sqrt(4+Exp(2)))/2; // G. C. Greubel, Oct 31 2018
  • Maple
    evalf((exp(1)+sqrt(4+exp(2)))/2,140); # Muniru A Asiru, Nov 01 2018
  • Mathematica
    r=E; t = (r + (4+r^2)^(1/2))/2; FullSimplify[t]
    N[t, 130]
    RealDigits[N[t, 130]][[1]]
    RealDigits[(E+Sqrt[4+E^2])/2,10,150][[1]] (* Harvey P. Dale, Jan 07 2015 *)
  • PARI
    default(realprecision, 100); (exp(1) + sqrt(4 + exp(2)))/2 \\ G. C. Greubel, Oct 31 2018
    

A188722 Decimal expansion of (Pi+sqrt(4+Pi^2))/2.

Original entry on oeis.org

3, 4, 3, 2, 8, 9, 2, 2, 1, 5, 9, 1, 3, 4, 8, 3, 2, 4, 4, 2, 0, 1, 4, 6, 0, 3, 7, 0, 2, 3, 5, 8, 1, 0, 9, 6, 6, 9, 0, 2, 7, 3, 4, 1, 0, 5, 8, 2, 0, 2, 4, 4, 4, 1, 9, 5, 1, 0, 1, 5, 2, 2, 2, 1, 9, 5, 8, 7, 9, 8, 8, 1, 1, 1, 4, 5, 4, 4, 9, 7, 0, 2, 3, 0, 4, 1, 2, 0, 2, 4, 6, 9, 6, 5, 7, 3, 3, 7, 8, 4, 4, 6, 2, 1, 6, 9, 9, 3, 2, 3, 2, 9, 8, 3, 6, 4, 2, 4, 4, 3, 3, 3, 0, 0, 7, 2, 7, 6, 8, 8
Offset: 1

Views

Author

Clark Kimberling, Apr 09 2011

Keywords

Comments

Decimal expansion of shape of a Pi-extension rectangle; see A188640 for definitions of shape and r-extension rectangle. Briefly, an r-extension rectangle is composed of two rectangles having shape r.
A Pi-extension rectangle matches the continued fraction A188723 of the shape L/W = (Pi+sqrt(4+Pi^2))/2. This is analogous to the matching of a golden rectangle to the continued fraction [1,1,1,1,1,1,1,...]. Specifically, for a Pi-extension rectangle, 3 squares are removed first, then 2 squares, then 3 squares, then 4 squares, then 2 squares,..., so that the original rectangle is partitioned into an infinite collection of squares.

Examples

			3.4328922159134832442014603702358109669027341058202444195...
		

Crossrefs

Programs

  • Mathematica
    r = Pi; t = (r + (4 + r^2)^(1/2))/2; FullSimplify[t]
    N[t, 130]
    RealDigits[N[t, 130]][[1]]
    ContinuedFraction[t, 120]
  • PARI
    (Pi+sqrt(4+Pi^2))/2 \\ Michel Marcus, Apr 01 2015

Formula

(Pi+sqrt(4+Pi^2))/2 = [Pi,Pi,Pi,...] (continued fraction). - Clark Kimberling, Sep 23 2013

A188725 Decimal expansion of shape of a (2*Pi)-extension rectangle; shape = Pi + sqrt(1 + Pi^2).

Original entry on oeis.org

6, 4, 3, 8, 5, 0, 0, 9, 6, 3, 0, 6, 5, 4, 0, 8, 3, 9, 7, 2, 2, 3, 2, 3, 2, 5, 6, 3, 5, 9, 4, 6, 9, 1, 7, 2, 9, 2, 6, 2, 1, 6, 6, 5, 4, 0, 8, 1, 3, 2, 6, 1, 5, 2, 5, 6, 1, 0, 6, 5, 1, 7, 3, 2, 5, 8, 9, 5, 9, 2, 1, 2, 6, 3, 3, 4, 3, 7, 5, 1, 1, 6, 9, 3, 8, 6, 9, 6, 6, 9, 2, 7, 7, 2, 1, 5, 3, 0, 9, 8, 5, 0, 0, 3, 9, 3, 0, 2, 8, 1, 2, 1, 5, 8, 5, 8, 7, 0, 2, 3, 1, 6, 7, 6, 5, 3, 0, 9, 1, 5
Offset: 1

Views

Author

Clark Kimberling, Apr 09 2011

Keywords

Comments

See A188640 for definitions of shape and r-extension rectangle. Briefly, an r-extension rectangle is composed of two rectangles of shape r.
A 2*Pi-extension rectangle matches the continued fraction [6,2,3,1,1,3,2,1,16,47,...] of the shape L/W = Pi + sqrt(1 + Pi^2). This is analogous to the matching of a golden rectangle to the continued fraction [1,1,1,1,1,1,1,...]. Specifically, for the (2*Pi)-extension rectangle, 6 squares are removed first, then 2 squares, then 3 squares, then 1 square, then 1 square, ..., so that the original rectangle is partitioned into an infinite collection of squares.

Examples

			6.4385009630654083972232325635946917292621665408132615256106...
		

Crossrefs

Programs

  • Magma
    SetDefaultRealField(RealField(100)); R:= RealField(); Pi(R) + Sqrt(1 + Pi(R)^2); // G. C. Greubel, Oct 31 2018
  • Maple
    evalf(Pi+sqrt(1+Pi^2),140); # Muniru A Asiru, Nov 01 2018
  • Mathematica
    r = 2*Pi; t = (r + (4 + r^2)^(1/2))/2; FullSimplify[t]
    N[t, 130]
    RealDigits[N[t, 130]][[1]] (* A188725 *)
    ContinuedFraction[t, 120] (* A188726 *)
    RealDigits[Pi + Sqrt[1 + Pi^2], 10, 100][[1]] (* G. C. Greubel, Oct 31 2018 *)
  • PARI
    default(realprecision, 100); Pi + sqrt(1 + Pi^2) \\ G. C. Greubel, Oct 31 2018
    

A188730 Decimal expansion of (2+sqrt(29))/5.

Original entry on oeis.org

1, 4, 7, 7, 0, 3, 2, 9, 6, 1, 4, 2, 6, 9, 0, 0, 8, 0, 6, 2, 5, 0, 1, 4, 2, 0, 9, 8, 3, 0, 8, 0, 6, 5, 9, 1, 1, 2, 5, 9, 0, 2, 4, 0, 3, 2, 3, 2, 8, 9, 5, 7, 7, 6, 7, 5, 3, 6, 0, 7, 7, 7, 3, 4, 0, 0, 3, 3, 2, 9, 1, 9, 2, 5, 6, 5, 5, 3, 1, 7, 3, 8, 5, 7, 5, 3, 2, 6, 7, 5, 6, 3, 3, 5, 9, 6, 7, 0, 9, 6, 8, 8, 3, 7, 4, 0, 9, 6, 4, 3, 5, 8, 7, 8, 9, 1, 5, 2, 1, 2, 1, 5, 3, 7, 7, 2, 4, 2, 8, 0
Offset: 1

Views

Author

Clark Kimberling, Apr 10 2011

Keywords

Comments

Decimal expansion of shape of a (4/5)-extension rectangle; see A188640 for definitions of shape and r-extension rectangle. Briefly, shape=length/width, and an r-extension rectangle is composed of two rectangles of shape 1/r when r<1.
The continued fractions of the constant are 1, 2, 10, 2, 1, 1, 2, 10, 2, 1, 1, 2, 10, 2, 1, 1, 2, 10, 2, 1, 1, 2...

Examples

			1.4770329614269008062501420983080659112590240323289577675360...
		

Crossrefs

Programs

  • Magma
    SetDefaultRealField(RealField(100)); (2+Sqrt(29))/5; // G. C. Greubel, Nov 01 2018
  • Maple
    evalf((2+sqrt(29))/5,140); # Muniru A Asiru, Nov 01 2018
  • Mathematica
    RealDigits[(2 + Sqrt[29])/5, 10, 111][[1]] (* Robert G. Wilson v, Aug 18 2011 *)
  • PARI
    default(realprecision, 100); (2+sqrt(29))/5 \\ G. C. Greubel, Nov 01 2018
    

A188934 Decimal expansion of (1+sqrt(17))/4.

Original entry on oeis.org

1, 2, 8, 0, 7, 7, 6, 4, 0, 6, 4, 0, 4, 4, 1, 5, 1, 3, 7, 4, 5, 5, 3, 5, 2, 4, 6, 3, 9, 9, 3, 5, 1, 9, 2, 5, 6, 2, 8, 6, 7, 9, 9, 8, 0, 6, 3, 4, 3, 4, 0, 5, 1, 0, 8, 5, 9, 9, 6, 5, 8, 3, 9, 3, 2, 7, 3, 7, 3, 8, 5, 8, 6, 5, 8, 4, 4, 0, 5, 3, 9, 8, 3, 9, 6, 9, 6, 5, 9, 1, 2, 7, 0, 2, 6, 7, 1, 0, 7, 4, 1, 7, 1, 1, 3, 6, 0, 1, 0, 2, 3, 4, 8, 0, 3, 5, 3, 5, 4, 0, 3, 8, 2, 5, 3, 5, 5, 2, 1, 0
Offset: 1

Views

Author

Clark Kimberling, Apr 13 2011

Keywords

Comments

Decimal expansion of the length/width ratio of a (1/2)-extension rectangle. See A188640 for definitions of shape and r-extension rectangle.
A (1/2)-extension rectangle matches the continued fraction [1,3,1,1,3,1,1,3,1,1,3,...] for the shape L/W=(1+sqrt(17))/4. This is analogous to the matching of a golden rectangle to the continued fraction [1,1,1,1,1,1,1,1,...]. Specifically, for the (1/2)-extension rectangle, 1 square is removed first, then 3 squares, then 1 square, then 1 square,..., so that the original rectangle of shape (1+sqrt(17))/4 is partitioned into an infinite collection of squares.
Conjecture: This number is an eigenvalue to infinitely many n*n submatrices of A191898, starting in the upper left corner, divided by the row index. For the first few characteristic polynomials see A260237 and A260238. - Mats Granvik, May 12 2016.

Examples

			1.2807764064044151374553524639935192562...
		

Crossrefs

Essentially the same as A188485.

Programs

  • Mathematica
    r = 1/2; t = (r + (4 + r^2)^(1/2))/2; RealDigits[ N[ FullSimplify@ t, 111]][[1]]
    (* for the continued fraction *) ContinuedFraction[t, 120]
    RealDigits[(1 + Sqrt@ 17)/4, 10, 111][[1]] (* Or *)
    RealDigits[Exp@ ArcSinh[1/4], 10, 111][[1]] (* Robert G. Wilson v, Aug 17 2011 *)
  • PARI
    (sqrt(17)+1)/4 \\ Charles R Greathouse IV, May 12 2016
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