A341060 Numbers k such that A340179(k) is a multiple of k.

1, 2, 10, 16, 30, 74, 81, 97, 489, 525, 607, 1861, 4439, 26051

Offset

1,2

Links

Table of n, a(n) for n=1..14.

Example

a(4) = 16 is a term because A340179(16) = 32 = 2*16.

Maple

f:= proc(n) local C, s, c;
  C:=select(t -> igcd(t, n) = 1, [$1..n-1]);
  s:= convert(C, `+`);
  add(s mod c, c = C)
end proc:
select(t -> f(t) mod t = 0, [$1..5000]);

Mathematica

A340179[n_] := Total@Mod[#2, #1]& @@ {#, Total@#}& @ Select[Range[n], GCD[#, n] == 1&];
Reap[For[k = 1, k <= 80000, k++, If[Divisible[A340179[k], k], Print[k]; Sow[k]]]][[2, 1]] (* Jean-François Alcover, May 16 2023, after Michael De Vlieger in A340179 *)

Crossrefs

Cf. A340179, A341059, A341061.

Sequence in context: A054028 A063716 A125212 * A189329 A242089 A110761

Adjacent sequences: A341057 A341058 A341059 * A341061 A341062 A341063

Keyword

nonn,more

Author

J. M. Bergot and Robert Israel, Feb 04 2021

Status

approved