%I A103288
%S A103288 1,2,4,6,8,12,16,18,20,24,28,30,32,36,40,42,48,54,56,60,64,66,70,72,78,
%T A103288 80,84,88,90,96,100,102,104,108,112,114,120,126,128,132,138,140,144,150,
%U A103288 156,160,162,168,174,176,180,186,192,196,198,200,204,208,210,216,220
%N A103288 Numbers n such that sigma(n) >= 2n-1 (union of perfect, abundant and 
               least deficient numbers).
%C A103288 If the only least deficient numbers are the powers of 2 (open problem) 
               then this sequence is a union of A023196 and A000079.
%F A103288 Such n that A004125(n) <= A004125(n-1)
%o A103288 (PARI) for(n=1,1000,if(sigma(n)>=2*n-1,print(n)));
%Y A103288 Cf. A023196, A023197, A023198, A023199, A000079, A004125.
%Y A103288 Sequence in context: A090404 A058825 A087086 this_sequence A125225 A092903 
               A005153
%Y A103288 Adjacent sequences: A103285 A103286 A103287 this_sequence A103289 A103290 
               A103291
%K A103288 nonn
%O A103288 1,2
%A A103288 Max Alekseyev (maxale(AT)gmail.com), Jan 28 2005