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 1-2 of 2 results.

A059546 Beatty sequence for log(10)/(log(10)-1).

Original entry on oeis.org

1, 3, 5, 7, 8, 10, 12, 14, 15, 17, 19, 21, 22, 24, 26, 28, 30, 31, 33, 35, 37, 38, 40, 42, 44, 45, 47, 49, 51, 53, 54, 56, 58, 60, 61, 63, 65, 67, 68, 70, 72, 74, 76, 77, 79, 81, 83, 84, 86, 88, 90, 91, 93, 95, 97, 98, 100, 102, 104, 106, 107, 109, 111, 113, 114, 116
Offset: 1

Views

Author

Mitch Harris, Jan 22 2001

Keywords

Crossrefs

Beatty complement is A059545.
Cf. A002392.

Programs

  • Mathematica
    Floor[Range[100]*(1 + 1/(Log[10] - 1))] (* Paolo Xausa, Jul 05 2024 *)
  • PARI
    { default(realprecision, 100); b=log(10)/(log(10) - 1); for (n = 1, 2000, write("b059546.txt", n, " ", floor(n*b)); ) } \\ Harry J. Smith, Jun 28 2009

Formula

a(n) = floor(n*log(10)/(log(10) - 1)). - Michel Marcus, Jan 04 2015

A334168 Numbers m whose leading digit and the other decimal digits appear respectively before and directly after the decimal point of its m-th root.

Original entry on oeis.org

1, 12, 104, 1006, 10009, 100011, 1000013, 10000016, 100000018, 1000000020, 10000000023, 100000000025, 1000000000027, 10000000000029, 100000000000032, 1000000000000034, 10000000000000036, 100000000000000039, 1000000000000000041, 10000000000000000043
Offset: 1

Views

Author

Alaa A. Nasr, Apr 17 2020

Keywords

Comments

These numbers m are equal to the integer part of their m-th root multiplied by 10 to the power of the number of digits of m-1.
The last nonzero digits of the terms are conjectured to be the Beatty sequence for log(10), A059545.

Examples

			12^(1/12) = 1.23007..., 104^(1/104) = 1.0457..., 100011^(1/100011) = 1.00011512...
		

Crossrefs

Cf. A059545.

Programs

  • PARI
    isok(m) = floor(10^(#Str(m)-1)*sqrtn(m, m)) == m; \\ Michel Marcus, Apr 17 2020
  • Python
    # for the first 6 terms
    import math
    for n in range(1, 1000000):
        if math.floor((n**(1/n))*10**(len(str(n))-1)) == n:
            print(n)
    

Formula

a(n+1) = floor((10^(n/10^n))*10^n) (conjectured).
a(n) = 10^(n-1) + floor((n-1)*log(10)) (conjectured). - David A. Corneth, Apr 19 2020

Extensions

More terms from David A. Corneth, Apr 19 2020
Showing 1-2 of 2 results.