A341045 Numbers k such that k divides A318996(k).

1, 4, 6, 28, 45, 120, 496, 672, 6048, 8128, 14421, 30240, 32760, 523776, 2178540, 23569920, 26409026, 29270772, 30685402, 33550336, 45532800

Offset

1,2

Links

Table of n, a(n) for n=1..21.

Example

a(2) = 4 is a term because A318996(4) = 4 is divisible by 4.
a(3) = 6 is a term because A318996(6) = 0 is divisible by 6.

Maple

f:= proc(n) local s, D, t;
  D:= numtheory:-divisors(n);
  s:= convert(D, `+`);
  add(s mod t, t=D)
end proc:
select(t -> f(t) mod t = 0, [$1..20000]);

Prog

(PARI) f(n) = my(sn = sigma(n)); sumdiv(n, d, sn % d); \\ A318996
isok(k) = !(f(k) % k); \\ Michel Marcus, Feb 03 2021

Crossrefs

Contains A007691.

Cf. A318996.

Sequence in context: A106286 A066293 A204385 * A050881 A229719 A122113

Adjacent sequences: A341042 A341043 A341044 * A341046 A341047 A341048

Keyword

nonn,more

Author

J. M. Bergot and Robert Israel, Feb 03 2021

Status

approved