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%I #12 Apr 09 2021 08:47:36
%S 0,0,1,0,0,1,1,0,0,1,1,1,0,1,1,0,1,0,1,1,1,1,1,1,0,1,1,1,1,1,1,1,1,1,
%T 1,0,0,1,1,1,0,1,1,1,1,1,1,1,0,0,1,1,1,1,1,1,1,1,1,1,0,1,1,0,1,1,1,1,
%U 1,1,1,1,0,1,1,1,1,1,1,1,0,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,1,0,0,1,1,1,1
%N a(n) = 1 if A003415(sigma(k)) > k, otherwise 0.
%H Antti Karttunen, <a href="/A343219/b343219.txt">Table of n, a(n) for n = 1..65537</a>
%H <a href="/index/Ch#char_fns">Index entries for characteristic functions</a>
%H <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%t Array[Boole[If[#2 < 2, 0, #2 Total[#2/#1 & @@@ FactorInteger[#2]]] > #1] & @@ {#, DivisorSigma[1, #]} &, 105] (* _Michael De Vlieger_, Apr 08 2021 *)
%o (PARI)
%o A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
%o A343219(n) = (A003415(sigma(n))>n);
%Y Cf. A000203, A003415, A343220, A343225.
%Y Characteristic function of A343218.
%K nonn
%O 1
%A _Antti Karttunen_, Apr 08 2021
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