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.

A381246 Largest value in trajectory of n under the juggler map of A380891.

Original entry on oeis.org

1, 2, 4, 4, 8, 6, 30, 8, 18, 10, 24, 12, 30, 14, 36, 16, 150, 18, 50, 20, 1320, 22, 43366048, 24, 41678, 26, 350, 28, 41678, 30, 234421146, 32, 2438232, 34, 114, 36, 5184, 38, 132, 40, 124026, 42, 150, 44, 160, 46, 934, 48, 1008, 50, 1084, 52, 43366048, 54, 1240
Offset: 1

Views

Author

James C. McMahon and Vikram Prasad, Apr 17 2025

Keywords

Comments

A380891(x) map is If x mod 2 = 0 then a(x) = floor(x^(1/3)) else a(x) = floor(x^(4/3)).

Crossrefs

Programs

  • Mathematica
    fj[n_]:=If[Mod[n,2]==0,Floor[Surd[n,3]],Floor[n^(4/3)]];a381246[n_]:=Max[Delete[FixedPointList[fj, n], -1]];Array[a381246,55]
  • Python
    import sys
    import gmpy2
    sys.set_int_max_str_digits(0)
    def floorJuggler(n):
        a=n
        max=n
        while a > 1:
            b=0
            if a%2 == 0:
                b1=gmpy2.iroot(a,3)
                b=b1[0]
            else:
                b1=gmpy2.iroot(a**4,3)
                b=b1[0]
            a=b
            if a > max:
                max = a
        return max
    maxcount=0
    for i in range (1, 100):
        print (i, floorJuggler(i))

A383135 a(n) = number of iterations that n requires to reach 1 under the x -> A380891(x) map, or -1 if it never does.

Original entry on oeis.org

0, 1, 2, 1, 3, 1, 5, 2, 3, 2, 3, 2, 4, 2, 4, 2, 6, 2, 4, 2, 6, 2, 13, 2, 13, 2, 8, 3, 8, 3, 10, 3, 10, 3, 3, 3, 10, 3, 5, 3, 10, 3, 5, 3, 5, 3, 6, 3, 5, 3, 5, 3, 17, 3, 5, 3, 5, 3, 17, 3, 3, 3, 3, 2, 12, 2, 3, 2, 5, 2, 5, 2, 12, 2, 3, 2, 7, 2, 3, 2, 7, 2, 7, 2
Offset: 1

Views

Author

James C. McMahon and Vikram Prasad, Apr 17 2025

Keywords

Comments

A380891(x) map is If x mod 2 = 0 then a(x) = floor(x^(1/3)) else a(x) = floor(x^(4/3)).
The map x -> A380891(x) is conjectured to eventually reach 1 for all starting x > 0. Tested for x <= 7892481.

Crossrefs

Programs

  • Mathematica
    fj[n_]:=If[Mod[n,2]==0,Floor[Surd[n,3]],Floor[n^(4/3)]];a383135[n_]:= Length[ NestWhileList[fj, n, # != 1 &]] - 1; Array[ a383135, 84]
  • Python
    import sys
    import gmpy2
    sys.set_int_max_str_digits(0)
    def floorJuggler(n) :
        a=n
        count=0
        while (a > 1) :
            b=0
            if (a%2 == 0) :
                b1=gmpy2.iroot(a,3)
                b=b1[0]
                count=count+1
            else :
                b1=gmpy2.iroot(a**4,3)
                b=b1[0]
                count=count+1
            a=b
        return count
    for i in range (1, 100) :
        print (i, floorJuggler(i))
Showing 1-2 of 2 results.