A371953 Weird numbers whose abundance is a weird number with weird abundance (A371952).

13516958630, 13662237610, 14483820470, 16161187910, 16266406870, 17187072770, 17779204310, 18055129190, 19265719130, 20027984690, 20291032090, 20945054548, 21036318170, 21395831170, 21983936030, 22134086030, 22335605390, 23837897510, 24709171970, 25630894310, 26286582910

Offset: 1

Author

Amiram Eldar, Apr 14 2024

Keywords

• nonn

Comments

Terms k of A006037 such that A033880(k) and A033880(A033880(k)) are also terms of A006037.

Are there numbers k such that k, A033880(k), A033880(A033880(k)), and A033880(A033880(A033880(k))) are all terms of A006037? There are none below 10^11.

Examples

			13516958630 is a term because it is a weird number, A033880(13516958630) = sigma(13516958630) - 2*13516958630 = 833308916 is a weird number, and A033880(833308916) = sigma(833308916) - 2*833308916 = 7975928 is also a weird number.
		

Links

• Amiram Eldar, Table of n, a(n) for n = 1..146 (terms below 10^11)
• Wikipedia, Weird number.

Crossrefs

Subsequence of A006037, A371920 and A371952.

Cf. A000203 (sigma), A033880 (abundance).