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A065202 Characteristic function of A065201: a(n) = if A065201(k) = n for some k then 1 else 0.

%I A065202 #21 Mar 19 2025 08:33:51
%S A065202 0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,1,0,0,0,1,0,0,0,1,0,0,0,0,0,0,
%T A065202 0,1,0,0,0,1,0,0,0,1,1,0,0,1,0,0,0,1,0,0,0,1,0,0,0,1,0,0,1,0,0,0,0,1,
%U A065202 0,0,0,1,0,0,0,1,0,0,0,1,0,0,0,1,0,0,0,1,0,1,0,1,0,0,0,1,0,0,1,1,0,0,0,1,0
%N A065202 Characteristic function of A065201: a(n) = if A065201(k) = n for some k then 1 else 0.
%H A065202 Antti Karttunen, <a href="/A065202/b065202.txt">Table of n, a(n) for n = 1..65537</a>
%H A065202 <a href="/index/Ch#char_fns">Index entries for characteristic functions</a>.
%F A065202 a(A065200(n)) = 0 and a(A065201(n)) = 1.
%F A065202 a(n) = A107078(A051119(n)). - _Antti Karttunen_, Aug 27 2017
%t A065202 a[n_] := If[Max[Most[FactorInteger[n][[;;, 2]]]] > 1, 1, 0]; Array[a, 100] (* _Amiram Eldar_, Mar 19 2025 *)
%o A065202 (PARI)
%o A065202 A053585(n) = if(n>1, my(f=factor(n)); f[#f~, 1]^f[#f~, 2], 1) \\ _Charles R Greathouse IV_, Nov 10 2015
%o A065202 A051119(n) = (n/A053585(n));
%o A065202 A065202(n) = (1-abs(moebius(A051119(n)))); \\ _Antti Karttunen_, Aug 27 2017
%o A065202 (PARI) a(n) = {my(e = factor(n)[,2]); #e > 1 && vecmax(e[1..#e-1]) > 1;} \\ _Amiram Eldar_, Mar 19 2025
%Y A065202 Cf. A051119, A053585, A065201, A065200, A070003, A107078.
%K A065202 nonn
%O A065202 1,1
%A A065202 _Reinhard Zumkeller_, Oct 21 2001
%E A065202 Edited by _Franklin T. Adams-Watters_, Oct 27 2006