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.

A249179 First row of spectral array W(3^(1/3)).

Original entry on oeis.org

1, 3, 4, 9, 12, 29, 41, 94, 135, 306, 441, 997, 1437, 3251, 4688, 10602, 15290, 34574, 49864, 112751, 162615, 367699, 530313, 1199127, 1729440, 3910553, 5639993, 12752965
Offset: 1

Views

Author

Colin Barker, Dec 03 2014

Keywords

Comments

3^(1/3) = 1.442249570307408382321638310780109588391869253499350577546416...
The sequence is generated from the Beatty sequence (A059539) and from the complement of the Beatty sequence (A059540) for 3^(1/3).

Crossrefs

Programs

  • PARI
    \\ Row i of the generalized Wythoff array W(h),
    \\   where h is an irrational number between 1 and 2,
    \\   and m is the number of terms in the vectors b and c.
    row(h, i, m) = {
      if(h<=1 || h>=2, print("Invalid value for h"); return);
      my(
        b=vector(m, n, floor(n*h)),       \\ Beatty sequence for h
        c=vector(m, n, floor(n*h/(h-1))), \\ Complement of b
        w=[b[b[i]], c[b[i]]],
        j=3
      );
      while(1,
        if(j%2==1,
          if(w[j-1]<=#b, w=concat(w, b[w[j-1]]), return(w))
        ,
          if(w[j-2]<=#c, w=concat(w, c[w[j-2]]), return(w))
        );
        j++
      )
    }
    allocatemem(10^9)
    default(realprecision, 100)
    row(3^(1/3), 1, 10^7)