A342503 Numbers k such that k divides A340740(k).

1, 2, 3, 4, 6, 19, 48, 111, 4630, 5428, 13569, 41628, 87659, 108990, 555716, 751863, 973813, 5124585, 8663699, 19545678, 24330343

Offset

1,2

Links

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

Example

a(8) = 111 is a term because 111 divides A340740(111) = 444.

Maple

filter:= proc(n) local k; add(`if`(igcd(k, n)=1, (n-k) mod k, 0), k=1..n/2) mod n = 0 end proc:
select(filter, [$1..10^5]);

Prog

(Python)
from math import gcd
A342503_list = [k for k in range(1, 10**4) if sum(k % i for i in range(1, k//2+1) if gcd(i, k) == 1) % k == 0] # Chai Wah Wu, Mar 18 2021

Crossrefs

Cf. A340740.

Sequence in context: A084391 A259383 A220702 * A369773 A217351 A274238

Adjacent sequences: A342500 A342501 A342502 * A342504 A342505 A342506

Keyword

nonn,more

Author

J. M. Bergot and Robert Israel, Mar 16 2021

Extensions

a(14)-a(17) from Chai Wah Wu, Mar 18 2021

a(18)-a(19) from Martin Ehrenstein, May 14 2021

a(20) from Kevin P. Thompson, Jan 19 2023

a(21) from Kevin P. Thompson, Feb 07 2023

Status

approved