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A371952
Weird numbers whose abundance is also a weird number.
3
12110, 1596770, 1629364, 4265590, 4442690, 6015310, 7122290, 7142030, 8438990, 8837570, 8877890, 9667910, 9989770, 10106810, 10867570, 11130910, 11306470, 11511290, 12008710, 12096490, 12623170, 12915770, 13281170, 13390510, 13852090, 14144690, 14583590, 14817670
OFFSET
1,1
COMMENTS
Terms k of A006037 such that A033880(k) is also a term of A006037.
LINKS
EXAMPLE
12110 is a term because it is a weird number, and A033880(12110) = sigma(12110) - 2*12110 = 836 is also a weird number.
MATHEMATICA
With[{weirds = Import["https://oeis.org/a006037/b006037.txt", "Table"][[;; , 2]]}, Select[weirds, (ab = DivisorSigma[1, #] - 2*#) <= Last[weirds] && MemberQ[weirds, ab] &]]
CROSSREFS
Subsequence of A006037 and A371920.
A371953 is a subsequence.
Cf. A000203 (sigma), A033880 (abundance), A371950.
Sequence in context: A257357 A070187 A031661 * A247403 A262635 A186564
KEYWORD
nonn
AUTHOR
Amiram Eldar, Apr 14 2024
STATUS
approved