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%I #4 May 15 2013 08:58:33
%S 1,4,5,8,10,16,18,22,23,27,29,32,36,41,46,50,53,65,66,70,94,99,101,
%T 106,111,113,125,129,131,137,171,183,195,197,200,201,203,209,210,221,
%U 233,237,239,245,251,269,275,299,301,309,317,321,322,327,329,333,335
%N n+sigma(n)+sigma(sigma(n)) is a prime.
%H Harvey P. Dale, <a href="/A116050/b116050.txt">Table of n, a(n) for n = 1..1000</a>
%e 8 + sigma(8) + sigma(sigma(8)) = 47.
%t dsQ[n_]:=Module[{dsn=DivisorSigma[1,n]},PrimeQ[n+dsn+DivisorSigma[1,dsn]]]; Select[Range[400],dsQ] (* _Harvey P. Dale_, May 15 2013 *)
%Y Cf. A078762.
%K nonn
%O 1,2
%A _Giovanni Resta_, Feb 13 2006