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%I #10 Jun 24 2014 01:08:22
%S 1,38184,458010,776112,65676408,1488668112,4414086384,28645019964,
%T 46696401675,65466785748,70619381496,176151711072
%N Numbers n such that sigma(n)+sigma(n+1)=4n.
%C a(13) > 10^13. - _Giovanni Resta_, Jul 11 2013
%t For[n=1, True, n++, If[DivisorSigma[1, n]+DivisorSigma[1, n+1]==4n, Print[n]]]
%Y Cf. A067806, A068078.
%K more,nonn
%O 1,2
%A _Dean Hickerson_, Feb 16 2002
%E a(6)-a(8) from _Donovan Johnson_, Jan 31 2009
%E a(9)-a(12) from _Giovanni Resta_, Jul 11 2013
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