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.

A130878 Inverse Moebius transform of A100107.

Original entry on oeis.org

1, 5, 6, 16, 13, 36, 31, 74, 87, 155, 201, 402, 523, 911, 1398, 2339, 3573, 5997, 9351, 15438, 24546, 40011, 64081, 104544, 167786, 272495, 439372, 712452, 1149853, 1863588, 3010351, 4875451, 7881606, 12759195, 20633323, 33397854, 54018523, 87422511, 141423378
Offset: 1

Views

Author

R. J. Mathar, Aug 21 2007

Keywords

Comments

Or, the inverse Moebius transform of the inverse Moebius transform of the Lucas numbers A000032.

Crossrefs

Programs

  • Maple
    A000032 := proc(n) option remember; if n =0 then 2; elif n = 1 then 1; else A000032(n-1)+A000032(n-2) ; fi ; end: A100107 := proc(n) option remember ; local a,dvs,d ; a := 0: dvs := numtheory[divisors](n) ; for d in dvs do a := a+ A000032(d) ; od: RETURN(a) ; end: a := proc(n) local a,dvs,d ; a := 0: dvs := numtheory[divisors](n) ; for d in dvs do a := a+ A100107(d) ; od: RETURN(a) ; end: seq(a(n),n=1..100);
    # second Maple program:
    a:= ((p-> j-> add(p(d), d=numtheory[divisors](j)))@@2)
         (n-> (<<1|1>, <1|0>>^n.<<2, -1>>)[1, 1]):
    seq(a(n), n=1..40);  # Alois P. Heinz, Jan 23 2024
  • Mathematica
    A100107[n_] := LucasL /@ Divisors[n] // Total;
    a[n_] := A100107 /@ Divisors[n] // Total;
    Table[a[n], {n, 1, 40}] (* Jean-François Alcover, Jan 23 2024 *)

Formula

a(n) = Sum_{d|n} A100107(d).