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%I #7 Dec 04 2024 20:54:22
%S 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
%T 0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
%U 0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0
%N Characteristic function of A083211: a(n) = 1 if n is abundant and is not Zumkeller, otherwise 0.
%H Antti Karttunen, <a href="/A378661/b378661.txt">Table of n, a(n) for n = 1..108045</a>
%H <a href="/index/Ch#char_fns">Index entries for characteristic functions</a>
%F a(n) = A294937(n) * (1-A179527(n)).
%F a(n) = [A378600(n) < 0].
%o (PARI) A378661(n) = ((sigma(n)>2*n) && (0==A083206(n)));
%Y Characteristic function of A083211, which is the intersection of A005101 and A083210.
%Y Cf. A000203, A083206, A179527, A294937, A378600.
%K nonn,new
%O 1
%A _Antti Karttunen_, Dec 04 2024