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%I #6 Aug 02 2013 14:22:20
%S 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,
%T 27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,
%U 50,51,52,53,54,55,56,57,58,59,60,62,63,64,65,66,67,68,69,70
%N Numbers n such that sigma(n-1) - sigma(n+1) < sigma(n); where sigma(n) = A000203(n) = sum of the divisors of n.
%C There is no number n < 100000 such that sigma(n-1) - sigma(n+1) = sigma(n).
%C Complement of A227980.
%H Jaroslav Krizek, <a href="/A227981/b227981.txt">Table of n, a(n) for n = 1..2000</a>
%e Number 60 is in the sequence because sigma(59) - sigma(61) = 60 - 62 = -2 < sigma(60) = 168.
%Y Cf. A000203, A227980.
%K nonn
%O 1,2
%A _Jaroslav Krizek_, Aug 02 2013