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A174897 a(n) = characteristic function of numbers k such that A007955(m) = k has solution for some m, where A007955(m) = product of divisors of m.

%I A174897 #15 Oct 21 2017 21:14:31
%S A174897 1,1,1,0,1,0,1,1,0,0,1,0,1,0,0,0,1,0,1,0,0,0,1,0,0,0,1,0,1,0,1,0,0,0,
%T A174897 0,1,1,0,0,0,1,0,1,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,1,0,1,0,0,1,0,0,1,0,
%U A174897 0,0,1,0,1,0,0,0,0,0,1,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,0,0,1,0,0,1,1,0,1,0,0
%N A174897 a(n) = characteristic function of numbers k such that A007955(m) = k has solution for some m, where A007955(m) = product of divisors of m.
%C A174897 a(n) = characteristic function of numbers from A174895(n).
%C A174897 a(n) = 1 if A007955(m) = n for any m, else 0.
%H A174897 Antti Karttunen, <a href="/A174897/b174897.txt">Table of n, a(n) for n = 1..65537</a>
%H A174897 <a href="/index/Ch#char_fns">Index entries for characteristic functions</a>
%F A174897 a(n) = 1 - A174898(n).
%t A174897 Block[{nn = 105, t}, t = ConstantArray[0, nn]; ReplacePart[t, Map[# -> 1 &, TakeWhile[Sort@ Array[Times @@ Divisors@ # &, nn], # <= 105 &]]]] (* _Michael De Vlieger_, Oct 20 2017 *)
%o A174897 (PARI)
%o A174897 up_to = 65537;
%o A174897 v174897 = vector(up_to);
%o A174897 A007955(n) = if(issquare(n, &n), n^numdiv(n^2), n^(numdiv(n)/2)); \\ This function from _Charles R Greathouse IV_, Feb 11 2011
%o A174897 for(k=1, up_to, t=A007955(k); if(t<=up_to, v174897[t] = 1));
%o A174897 write_to_bfile(start_offset,vec,bfilename) = { for(n=1, length(vec), write(bfilename, (n+start_offset)-1, " ", vec[n])); }
%o A174897 write_to_bfile(1,v174897,"b174897_upto65537.txt");
%o A174897 \\ _Antti Karttunen_, Oct 20 2017
%Y A174897 Cf. A007955, A174895, A174898.
%K A174897 nonn
%O A174897 1,1
%A A174897 _Jaroslav Krizek_, Apr 01 2010
%E A174897 Name edited and more terms added by _Antti Karttunen_, Oct 20 2017