A182227 Sum of divisors of the abundant number m = A005101(n) which are smaller than its abundance A033880(m).

6, 3, 1, 24, 27, 55, 20, 19, 76, 21, 14, 108, 23, 3, 123, 12, 66, 140, 3, 144, 156, 22, 12, 1, 172, 52, 12, 240, 123, 204, 12, 126, 259, 147, 236, 138, 66, 312, 12, 42, 546, 12, 316, 7, 171, 165, 198, 44, 366, 384, 174, 12, 112, 218, 117, 744, 12, 476, 12, 198

Offset: 1

Author

M. F. Hasler, Apr 19 2012

Keywords

• nonn

Comments

Motivated by A100696. See also A182225 and A182226.

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000 (terms 1..1000 from M. F. Hasler)

Crossrefs

Cf. A005101, A033880, A100696, A182225, A182226.

Programs

Mathematica

f[n_] := If[(ab = DivisorSigma[1, n] - 2*n) > 0 ,DivisorSum[n, # &, # < ab &],Nothing]; Array[f, 300] (* Amiram Eldar, Apr 06 2024 *)

PARI

f(n)=my(A=sigma(n)-2*n,s);fordiv(n,d,(d2*n & print1(f(n)","))