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 18 results. Next

A196737 Decimal expansion of (4*Pi^2)/sqrt(35) = A212002/A010490.

Original entry on oeis.org

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

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Author

Raphie Frank, Dec 21 2012

Keywords

Comments

This sequence is exactly equal to (Pi*h)/Spin(5/2), where h = Planck's Constant = A003676 and Spin(n/2) = h/(4*Pi) * sqrt(n(n+2)) = A003676/(10*A019694) * sqrt(A005563(n)).

Examples

			6.673070521654371272396016391388419924371668300691857264579256516590541...
		

Crossrefs

Programs

  • Mathematica
    RealDigits[(4Pi^2)/Sqrt[35],10,120][[1]] (* Harvey P. Dale, Jan 26 2021 *)

A248262 Egyptian fraction representation of sqrt(35) (A010490) using a greedy function.

Original entry on oeis.org

5, 2, 3, 13, 172, 106165, 18285649425, 2186743227575352844102, 34485253453894276212351220254887863775700566, 1196120890861075329034546890130985440938005448458845105688952404014155813652248242764257
Offset: 0

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Author

Robert G. Wilson v, Oct 04 2014

Keywords

Crossrefs

Egyptian fraction representations of the square roots: A006487, A224231, A248235-A248322.
Egyptian fraction representations of the cube roots: A129702, A132480-A132574.

Programs

  • Mathematica
    Egyptian[nbr_] := Block[{lst = {IntegerPart[nbr]}, cons = N[ FractionalPart[ nbr], 2^20], denom, iter = 8}, While[ iter > 0, denom = Ceiling[ 1/cons]; AppendTo[ lst, denom]; cons -= 1/denom; iter--]; lst]; Egyptian[ Sqrt[ 35]]

A090656 Decimal expansion of 5 + sqrt(35).

Original entry on oeis.org

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

Views

Author

Felix Tubiana, Feb 05 2004

Keywords

Comments

Equals n+n/(n+n/(n+n/(n+....))) for n = 10. See also A090388. - Stanislav Sykora, Jan 23 2014

Examples

			10.9160797830996160...
		

Crossrefs

Equals A010490 plus 5. - R. J. Mathar, Sep 08 2008
Cf. A161321.
Cf. n+n/(n+n/(n+...)): A090388 (n=2), A090458 (n=3), A090488 (n=4), A090550 (n=5), A092294 (n=6), A092290 (n=7), A090654 (n=8), A090655 (n=9). - Stanislav Sykora, Jan 23 2014

Programs

A041059 Denominators of continued fraction convergents to sqrt(35).

Original entry on oeis.org

1, 1, 11, 12, 131, 143, 1561, 1704, 18601, 20305, 221651, 241956, 2641211, 2883167, 31472881, 34356048, 375033361, 409389409, 4468927451, 4878316860, 53252096051, 58130412911, 634556225161, 692686638072, 7561422605881, 8254109243953, 90102515045411
Offset: 0

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Author

Keywords

Comments

The following remarks assume an offset of 1. This is the sequence of Lehmer numbers U_n(sqrt(R),Q) for the parameters R = 10 and Q = -1; it is a strong divisibility sequence, that is, gcd(a(n),a(m)) = a(gcd(n,m)) for all positive integers n and m. Consequently, this is a divisibility sequence: if n divides m then a(n) divides a(m). - Peter Bala, May 28 2014

Crossrefs

Programs

  • Mathematica
    Denominator[Convergents[Sqrt[35], 30]] (* Vincenzo Librandi, Oct 23 2013 *)

Formula

G.f.: (1+x-x^2)/(1-12*x^2+x^4). - Colin Barker, Jan 01 2012
From Peter Bala, May 28 2014: (Start)
The following remarks assume an offset of 1.
Let alpha = ( sqrt(10) + sqrt(14) )/2 and beta = ( sqrt(10) - sqrt(14) )/2 be the roots of the equation x^2 - sqrt(10)*x - 1 = 0. Then a(n) = (alpha^n - beta^n)/(alpha - beta) for n odd, while a(n) = (alpha^n - beta^n)/(alpha^2 - beta^2) for n even.
a(n) = Product_{k = 1..floor((n-1)/2)} ( 10 + 4*cos^2(k*Pi/n) ).
Recurrence equations: a(0) = 0, a(1) = 1 and for n >= 1, a(2*n) = a(2*n - 1) + a(2*n - 2) and a(2*n + 1) = 10*a(2*n) + a(2*n - 1). (End)

A040029 Continued fraction for sqrt(35).

Original entry on oeis.org

5, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 1, 10, 1
Offset: 0

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Author

Keywords

Examples

			5.9160797830996160425673282... = 5 + 1/(1 + 1/(10 + 1/(1 + 1/(10 + ...)))). - _Harry J. Smith_, Jun 04 2009
		

References

  • James J. Tattersall, Elementary Number Theory in Nine Chapters, Cambridge University Press, 1999, pages 275-276.

Crossrefs

Cf. A010490 (decimal expansion), A010691.

Programs

  • Maple
    Digits := 100: convert(evalf(sqrt(N)),confrac,90,'cvgts'):
  • Mathematica
    ContinuedFraction[Sqrt[35],300] (* Vladimir Joseph Stephan Orlovsky, Mar 06 2011 *)
    PadRight[{5},120,{10,1}] (* Harvey P. Dale, Mar 23 2021 *)
  • PARI
    { allocatemem(932245000); default(realprecision, 22000); x=contfrac(sqrt(35)); for (n=0, 20000, write("b040029.txt", n, " ", x[n+1])); } \\ Harry J. Smith, Jun 04 2009

Formula

From Amiram Eldar, Nov 12 2023: (Start)
Multiplicative with a(2^e) = 10, and a(p^e) = 1 for an odd prime p.
Dirichlet g.f.: zeta(s) * (1 + 9/2^s). (End)
G.f.: (5 + x + 5*x^2)/(1 - x^2). - Stefano Spezia, Jul 27 2025

A171543 Decimal expansion of 2/sqrt(35).

Original entry on oeis.org

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

Views

Author

R. J. Mathar, Dec 11 2009

Keywords

Comments

The absolute value of the Clebsch-Gordan coupling coefficient = <2 3/2 ; -1 3/2 | 7/2 1/2>.

Examples

			sqrt(4/35) = 2/sqrt(35) = 0.33806170189140663100384733094637811705...
		

Crossrefs

Programs

Formula

Equals 2/A010490 = A171538/2.

A010606 Decimal expansion of cube root of 35.

Original entry on oeis.org

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

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Author

Keywords

Crossrefs

Cf. A010490 (sqrt(35)).

Programs

A041058 Numerators of continued fraction convergents to sqrt(35).

Original entry on oeis.org

5, 6, 65, 71, 775, 846, 9235, 10081, 110045, 120126, 1311305, 1431431, 15625615, 17057046, 186196075, 203253121, 2218727285, 2421980406, 26438531345, 28860511751, 315043648855, 343904160606, 3754085254915
Offset: 0

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Author

Keywords

Crossrefs

Programs

Formula

a(n) = 12*a(n-2)-a(n-4). G.f.: (5+6*x+5*x^2-x^3)/(1-12*x^2+x^4). [Colin Barker, Apr 17 2012]

A161321 Decimal expansion of (sqrt(35)-5)/10.

Original entry on oeis.org

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

Views

Author

N. J. A. Sloane, Nov 22 2009

Keywords

Examples

			.091607978309961604256732829156161704841550123079434032287971...
		

References

  • D. Mumford et al., Indra's Pearls, Cambridge 2002; see p. 321.

Crossrefs

Programs

A171538 Decimal expansion of 4/sqrt(35).

Original entry on oeis.org

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

Views

Author

R. J. Mathar, Dec 11 2009

Keywords

Comments

The absolute value of the Clebsch-Gordan coupling coefficient = <2 3/2 ; -2 1/2 | 5/2 -3/2>.

Examples

			sqrt(16/35) = 0.67612340378281326200769466...
		

Programs

  • Mathematica
    RealDigits[4/Sqrt[35],10,120][[1]] (* Harvey P. Dale, Mar 29 2018 *)

Formula

equals 4/A010490 = 2*A171543 .
Showing 1-10 of 18 results. Next