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%I #20 Feb 08 2015 10:30:00
%S 27,1615,1885,218984,4218475,312016315,746314601,1125845307,
%T 1132343549,1296114929,9016730984,303419868239,1197056419121,
%U 2065971192041,2948269852109,4562970154601
%N Composite solutions to sigma(x)+8 = sigma(x+8).
%C a(17) > 10^13. - _Giovanni Resta_, Jul 11 2013
%D The first 4 terms were found by _Labos Elemer_, see A015915.
%e sigma(27)+8 = 48 = sigma(27+8), so 27 is in the sequence.
%t ta={{0}};Do[If[Equal[DivisorSigma[1, n+8] -DivisorSigma[1, n]-8, 0]&&!PrimeQ[n], Print[n]; ta=Append[ta, n]], {n, 1000000000, 1300000000}]; ta=Delete[ta, 1] (* _Labos Elemer_, Jan 10 2005 *)
%Y Cf. A015915.
%K nonn,more
%O 1,1
%A _Jud McCranie_, Jan 06 2001
%E a(8)-a(10) terms from _Labos Elemer_, Jan 10 2005
%E Offset corrected and a(11) added by _Donovan Johnson_, Dec 07 2008
%E a(12)-a(16) from _Giovanni Resta_, Jul 11 2013
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