cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A182226 Abundant numbers m (in A005101) whose sum of divisors less than their abundance A033880(m) does not exceed A033880(m).

This page as a plain text file.
%I A182226 #8 Sep 08 2019 02:42:17
%S A182226 18,20,70,78,88,102,104,114,138,174,186,196,222,246,258,282,318,354,
%T A182226 366,368,402,426,438,464,474,498,534,582,606,618,642,650,654,678,762,
%U A182226 786,822,834,836,894,906,942,978,1002,1014,1038,1074,1086,1146,1158,1182,1194,1266,1338,1362,1374,1398
%N A182226 Abundant numbers m (in A005101) whose sum of divisors less than their abundance A033880(m) does not exceed A033880(m).
%C A182226 Complement of A182225 in A005101.
%H A182226 Amiram Eldar, <a href="/A182226/b182226.txt">Table of n, a(n) for n = 1..10000</a>
%t A182226 aQ[n_] := (ab = DivisorSigma[1, n] - 2 n) > 0 && DivisorSum[n, # &, # < ab &] <= ab; Select[Range[1400], aQ] (* _Amiram Eldar_, Sep 08 2019 *)
%o A182226 (PARI) for(n=1,1999,sigma(n)>2*n||next;is_A182225(n)||print1(n","))
%K A182226 nonn
%O A182226 1,1
%A A182226 _M. F. Hasler_, Apr 19 2012