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%I #5 Aug 02 2013 14:21:56
%S 61,73,121,145,181,193,217,241,253,301,313,337,361,397,421,433,457,
%T 481,505,541,577,601,613,625,631,661,673,721,757,781,793,817,841,865,
%U 901,913,925,937,961,1009,1021,1051,1057,1081,1093,1141,1153,1171,1177,1201
%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 A227981.
%H Jaroslav Krizek, <a href="/A227980/b227980.txt">Table of n, a(n) for n = 1..2000</a>
%e Number 61 is in the sequence because sigma(60) - sigma(62) = 168 - 96 = 72 > sigma(61) = 62.
%Y Cf. A000203, A227981.
%K nonn
%O 1,1
%A _Jaroslav Krizek_, Aug 02 2013
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