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.

A241667 Sum of the iterates of A058026 up to and including either 0 or 1.

Original entry on oeis.org

0, 0, 1, 0, 4, 0, 9, 0, 4, 0, 13, 0, 24, 0, 4, 0, 19, 0, 36, 0, 9, 0, 30, 0, 19, 0, 13, 0, 40, 0, 69, 0, 13, 0, 19, 0, 54, 0, 24, 0, 63, 0, 104, 0, 13, 0, 58, 0, 54, 0, 19, 0, 70, 0, 40, 0, 36, 0, 93, 0, 152, 0, 19, 0, 46, 0, 111, 0, 30, 0, 99, 0, 170, 0, 19
Offset: 1

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Author

Colin Defant, Apr 26 2014

Keywords

Comments

It is interesting to note that a(37147) = 37147.
Also a(53290831) = 53290831. - Michel Marcus, Jun 18 2015

Examples

			A058026(7)=5, A058026(5)=3, A058026(3)=1, so a(7)=5+3+1=9. A058026(4)=0, so a(4)=0.
		

Programs

  • Mathematica
    L[n_, m_] :=
    If[Min[Select[Divisors[n], PrimeQ]] <= m, 0,
      n*Times @@ (1 - m/(Select[Divisors[n], PrimeQ]))]
    a[0] := 0
    a[3] := 1
    a[n_] := L[n, 2] + a[L[n, 2]]
    Table[a[i], {i, 2, 30}]
  • PARI
    a058026(n) = sumdiv(n, d, n/d*moebius(d)*numdiv(d));
    a(n) = {s = 0; itn = n; while((itn) && (itn != 1), vb = a058026(itn); s += vb; itn = vb); s;} \\ Michel Marcus, May 21 2014