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 1-3 of 3 results.

A105424 The part of n in base phi left of the decimal point, using a greedy algorithm representation (more precisely, using the Bergman-canonical representation).

Original entry on oeis.org

0, 1, 10, 100, 101, 1000, 1010, 10000, 10001, 10010, 10100, 10101, 100000, 100010, 100100, 100101, 101000, 101010, 1000000, 1000001, 1000010, 1000100, 1000101, 1001000, 1001010, 1010000, 1010001, 1010010, 1010100, 1010101, 10000000
Offset: 0

Views

Author

Bryan Jacobs (bryanjj(AT)gmail.com), Apr 08 2005

Keywords

Examples

			2 = 10.01 in base phi, so left of the decimal point is 10.
The first few numbers written in base phi:
0 = 0.
1 = 1.
2 = 10.01
3 = 100.01
4 = 101.01
5 = 1000.1001
6 = 1010.0001
7 = 10000.0001
8 = 10001.0001
9 = 10010.0101
10 = 10100.0101
11 = 10101.0101
12 = 100000.101001
13 = 100010.001001
14 = 100100.001001
15 = 100101.001001
16 = 101000.100001
17 = 101010.000001
18 = 1000000.000001
19 = 1000001.000001
20 = 1000010.010001
21 = 1000100.010001
22 = 1000101.010001
23 = 1001000.100101
24 = 1001010.000101
...
		

Crossrefs

See A341722 for the part to the right of the decimal point.
Cf. A105116 (base e), A344939 (base Pi).

Programs

  • Mathematica
    nn = 1000; len = 2*Ceiling[Log[GoldenRatio, nn]]; Table[d = RealDigits[n, GoldenRatio, len]; FromDigits[Take[d[[1]], d[[2]]]], {n, 0, nn}] (* T. D. Noe, May 20 2011 *)

Extensions

Definition clarified by N. J. A. Sloane, May 27 2023

A344939 The part of n left of the radix point when written in base Pi using a greedy algorithm representation.

Original entry on oeis.org

0, 1, 2, 3, 10, 11, 12, 20, 21, 22, 100, 101, 102, 103, 110, 111, 112, 120, 121, 122, 200, 201, 202, 210, 211, 212, 213, 220, 221, 222, 300, 301, 1000, 1001, 1002, 1010, 1011, 1012, 1020, 1021, 1022, 1100, 1101, 1102, 1103, 1110, 1111, 1112, 1120, 1121, 1122
Offset: 0

Views

Author

Paolo Xausa, Jun 03 2021

Keywords

Examples

			a(5) = 11 because 5 in base Pi is 11.22012202...
		

Crossrefs

Cf. A000796 (Pi digits). Subsequence of A007090.
Cf. A105116 (base e), A105424 (base phi).
Cf. A366721 (number of digits).

Programs

  • Maple
    A344939 := proc(n)
        local e,ntrunc,a,d;
        Digits := 1000 ;
        if n = 0 then
            return 0 ;
        end if;
        ntrunc := n ;
        e := floor(log(n)/log(Pi)) ;
        a := 0 ;
        while e >= 0 do
            d := floor(ntrunc/Pi^e) ;
            a := 10*a+d ;
            ntrunc := evalf(ntrunc-d*Pi^e) ;
            e := e-1 ;
        end do:
        a ;
    end proc:
    seq(A344939(n),n=0..15) ; # R. J. Mathar, Aug 16 2021
  • Mathematica
    A344939[n_]:=FromDigits[First[RealDigits[n,Pi,Floor[Log[Pi,Max[n,1]]]+1]]];
    Array[A344939,100,0] (* Paolo Xausa, Oct 17 2023 *)

Extensions

Name edited by Paolo Xausa, Oct 18 2023

A363832 Number of digits left of the radix point of n when written in base e using a greedy algorithm representation.

Original entry on oeis.org

1, 1, 1, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5
Offset: 0

Views

Author

Paolo Xausa, Oct 19 2023

Keywords

Comments

Essentially the same as A004233. - R. J. Mathar, Oct 23 2023

Examples

			a(10) = 3 because 10 in base e (102.11201...) has 3 digits before the radix point.
		

Crossrefs

Programs

  • Mathematica
    A363832[n_]:=Floor[Log[E,Max[n,1]]]+1;Array[A363832,100,0]

Formula

a(0) = 1; for n >= 1, a(n) = floor(log_e(n)) + 1.
Showing 1-3 of 3 results.