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.

Previous Showing 11-19 of 19 results.

A154859 Decimal expansion of log_9 (17).

Original entry on oeis.org

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

Views

Author

N. J. A. Sloane, Oct 30 2009

Keywords

Examples

			1.2894509615812829467581871223200888222408771473697233947468...
		

Crossrefs

Cf. decimal expansion of log_9(m): A152747 (m=2), A153205 (m=5), A153495 (m=6), A153619 (m=7), A153756 (m=8), A154160 (m=10), A154181 (m=11), A154202 (m=12), A154339 (m=13), A154469 (m=14), A154578 (m=15), this sequence, A154947 (m=18), A155061 (m=19), A155503 (m=20), A155676 (m=21), A155743 (m=22), A155829 (m=23), A155976 (m=24).

Programs

  • Magma
    SetDefaultRealField(RealField(100)); Log(17)/Log(9); // G. C. Greubel, Sep 01 2018
  • Mathematica
    RealDigits[Log[9, 17], 10, 100][[1]] (* Vincenzo Librandi, Sep 01 2013 *)
  • PARI
    default(realprecision, 100); log(17)/log(9) \\ G. C. Greubel, Sep 01 2018
    

A154947 Decimal expansion of log_9 (18).

Original entry on oeis.org

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

Views

Author

N. J. A. Sloane, Oct 30 2009

Keywords

Examples

			1.3154648767857287185497635571713804271497928200659402139353...
		

Crossrefs

Cf. decimal expansion of log_9(m): A152747 (m=2), A153205 (m=5), A153495 (m=6), A153619 (m=7), A153756 (m=8), A154160 (m=10), A154181 (m=11), A154202 (m=12), A154339 (m=13), A154469 (m=14), A154578 (m=15), A154859 (m=17), this sequence, A155061 (m=19), A155503 (m=20), A155676 (m=21), A155743 (m=22), A155829 (m=23), A155976 (m=24).

Programs

  • Magma
    SetDefaultRealField(RealField(100)); Log(18)/Log(9); // G. C. Greubel, Sep 01 2018
  • Mathematica
    RealDigits[Log[9, 18], 10, 100][[1]] (* Vincenzo Librandi, Sep 01 2013 *)
  • PARI
    default(realprecision, 100); log(18)/log(9) \\ G. C. Greubel, Sep 01 2018
    

Formula

Equals 1+A152747. - R. J. Mathar, Jan 07 2021
Equals A153495+1/2. - R. J. Mathar, Feb 15 2025

A155061 Decimal expansion of log_9 (19).

Original entry on oeis.org

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

Views

Author

N. J. A. Sloane, Oct 30 2009

Keywords

Examples

			1.3400719296231876724252833101095975652330714213471766109184...
		

Crossrefs

Cf. decimal expansion of log_9(m): A152747 (m=2), A153205 (m=5), A153495 (m=6), A153619 (m=7), A153756 (m=8), A154160 (m=10), A154181 (m=11), A154202 (m=12), A154339 (m=13), A154469 (m=14), A154578 (m=15), A154859 (m=17), A154947 (m=18), this sequence, A155503 (m=20), A155676 (m=21), A155743 (m=22), A155829 (m=23), A155976 (m=24).

Programs

  • Magma
    SetDefaultRealField(RealField(100)); Log(19)/Log(9); // G. C. Greubel, Sep 01 2018
  • Mathematica
    RealDigits[Log[9, 19], 10, 100][[1]] (* Vincenzo Librandi, Sep 01 2013 *)
  • PARI
    default(realprecision, 100); log(19)/log(9) \\ G. C. Greubel, Sep 01 2018
    

A155503 Decimal expansion of log_9 (20).

Original entry on oeis.org

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

Views

Author

N. J. A. Sloane, Oct 30 2009

Keywords

Examples

			1.3634165139304210206980473181820810524535518234649052723971...
		

Crossrefs

Cf. decimal expansion of log_9(m): A152747 (m=2), A153205 (m=5), A153495 (m=6), A153619 (m=7), A153756 (m=8), A154160 (m=10), A154181 (m=11), A154202 (m=12), A154339 (m=13), A154469 (m=14), A154578 (m=15), A154859 (m=17), A154947 (m=18), A155061 (m=19), this sequence, A155676 (m=21), A155743 (m=22), A155829 (m=23), A155976 (m=24).

Programs

  • Magma
    SetDefaultRealField(RealField(100)); Log(20)/Log(9); // G. C. Greubel, Sep 01 2018
  • Mathematica
    RealDigits[Log[9, 20], 10, 100][[1]] (* Vincenzo Librandi, Sep 01 2013 *)
  • PARI
    default(realprecision, 100); log(20)/log(9) \\ G. C. Greubel, Sep 01 2018
    

A155676 Decimal expansion of log_9 (21).

Original entry on oeis.org

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

Views

Author

N. J. A. Sloane, Oct 30 2009

Keywords

Examples

			1.3856218745807111300339641535412288590332356672971217396844...
		

Crossrefs

Cf. decimal expansion of log_9(m): A152747 (m=2), A153205 (m=5), A153495 (m=6), A153619 (m=7), A153756 (m=8), A154160 (m=10), A154181 (m=11), A154202 (m=12), A154339 (m=13), A154469 (m=14), A154578 (m=15), A154859 (m=17), A154947 (m=18), A155061 (m=19), A155503 (m=20), thus sequence, A155743 (m=22), A155829 (m=23), A155976 (m=24).

Programs

  • Magma
    SetDefaultRealField(RealField(100)); Log(21)/Log(9); // G. C. Greubel, Sep 01 2018
  • Mathematica
    RealDigits[Log[9,21],10,120][[1]] (* Harvey P. Dale, May 04 2012 *)
  • PARI
    default(realprecision, 100); log(21)/log(9) \\ G. C. Greubel, Sep 01 2018
    

A155743 Decimal expansion of log_9 (22).

Original entry on oeis.org

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

Views

Author

N. J. A. Sloane, Oct 30 2009

Keywords

Examples

			1.4067940461077977590742537645373448889212735826664123940539...
		

Crossrefs

Cf. decimal expansion of log_9(m): A152747 (m=2), A153205 (m=5), A153495 (m=6), A153619 (m=7), A153756 (m=8), A154160 (m=10), A154181 (m=11), A154202 (m=12), A154339 (m=13), A154469 (m=14), A154578 (m=15), A154859 (m=17), A154947 (m=18), A155061 (m=19), A155503 (m=20), A155676 (m=21), this sequence, A155829 (m=23), A155976 (m=24).

Programs

  • Magma
    SetDefaultRealField(RealField(100)); Log(22)/Log(9); // G. C. Greubel, Sep 01 2018
  • Mathematica
    RealDigits[Log[9, 22], 10, 100][[1]] (* Vincenzo Librandi, Sep 01 2013 *)
  • PARI
    default(realprecision, 100); log(22)/log(9) \\ G. C. Greubel, Sep 01 2018
    

A155829 Decimal expansion of log_9 (23).

Original entry on oeis.org

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

Views

Author

N. J. A. Sloane, Oct 30 2009

Keywords

Examples

			1.4270249151001355537018158824746039413815908185252448835867...
		

Crossrefs

Cf. decimal expansion of log_9(m): A152747 (m=2), A153205 (m=5), A153495 (m=6), A153619 (m=7), A153756 (m=8), A154160 (m=10), A154181 (m=11), A154202 (m=12), A154339 (m=13), A154469 (m=14), A154578 (m=15), A154859 (m=17), A154947 (m=18), A155061 (m=19), A155503 (m=20), A155676 (m=21), A155743 (m=22), this sequence, A155976 (m=24).

Programs

  • Magma
    SetDefaultRealField(RealField(100)); Log(23)/Log(9); // G. C. Greubel, Sep 01 2018
  • Mathematica
    RealDigits[Log[9, 23], 10, 100][[1]] (* Vincenzo Librandi, Sep 01 2013 *)
  • PARI
    default(realprecision, 100); log(23)/log(9) \\ G. C. Greubel, Sep 01 2018
    

A155976 Decimal expansion of log_9 (24).

Original entry on oeis.org

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

Views

Author

N. J. A. Sloane, Oct 30 2009

Keywords

Examples

			1.4463946303571861556492906715141412814493784601978206418059...
		

Crossrefs

Cf. decimal expansion of log_9(m): A152747 (m=2), A153205 (m=5), A153495 (m=6), A153619 (m=7), A153756 (m=8), A154160 (m=10), A154181 (m=11), A154202 (m=12), A154339 (m=13), A154469 (m=14), A154578 (m=15), A154859 (m=17), A154947 (m=18), A155061 (m=19), A155503 (m=20), A155676 (m=21), A155743 (m=22), A155829 (m=23), this sequence.

Programs

  • Magma
    SetDefaultRealField(RealField(100)); Log(24)/Log(9); // G. C. Greubel, Sep 01 2018
  • Mathematica
    RealDigits[Log[9, 24], 10, 100][[1]] (* Vincenzo Librandi, Sep 01 2013 *)
  • PARI
    default(realprecision, 100); log(24)/log(9) \\ G. C. Greubel, Sep 01 2018
    

A022331 Index of 2^n within sequence of numbers of form 2^i*3^j (A003586).

Original entry on oeis.org

1, 2, 4, 6, 9, 13, 17, 22, 28, 34, 41, 48, 56, 65, 74, 84, 95, 106, 118, 130, 143, 157, 171, 186, 202, 218, 235, 253, 271, 290, 309, 329, 350, 371, 393, 416, 439, 463, 487, 512, 538, 564, 591, 619, 647, 676, 706, 736, 767, 798, 830, 863, 896, 930, 965, 1000, 1036, 1072
Offset: 0

Views

Author

Keywords

Crossrefs

Cf. A000079, A003586, A071521, A020915 (first differences), A152747.
Cf. A022330 (index of 3^n within A003586).

Programs

  • Mathematica
    c[0] = 1; c[n_] := 1 + Sum[Ceiling[j*Log[3, 2]], {j, n}]; Table[c[i], {i, 0, 60}] (* Norman Carey, Jun 13 2012 *)
  • PARI
    a(n)=my(t=1);1+n+sum(k=1,n,logint(t*=2,3)) \\ Ruud H.G. van Tol, Nov 25 2022
    
  • Python
    from sympy import integer_log
    def A022331(n):
        m = 1<Chai Wah Wu, Sep 16 2024

Formula

a(n) = A071521(A000079(n)); A003586(a(n)) = A000079(n). - Reinhard Zumkeller, May 09 2006
a(n) ~ c * n^2, where c = log(2)/(2*log(3)) (A152747). - Amiram Eldar, Apr 07 2023
Previous Showing 11-19 of 19 results.