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%I #7 Mar 12 2019 22:23:41
%S 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,1,0,0,0,0,0,0,0,0,0,
%T 1,0,0,0,1,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,1,0,1,0,0,0,0,0,0,0,0,0,0,0,
%U 0,0,0,0,0,0,0,0,1,0,0,0,1,0,0,0,1,0,1,0,0,0,1,0,0,0,1,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,1,0,0,0,1,0,0,0,0,0
%N Characteristic function of A324551: a(n) = 1 if 2*A156552(n) < A323243(n), and 0 otherwise.
%H Antti Karttunen, <a href="/A324731/b324731.txt">Table of n, a(n) for n = 1..10000</a> (based on Hans Havermann's factorization of A156552)
%H <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>
%H <a href="/index/Ch#char_fns">Index entries for characteristic functions</a>
%H <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>
%F a(n) = 1 if A323244(n) is negative, and 0 otherwise.
%F For n > 1, a(n) = A294937(A156552(n)).
%o (PARI) A324731(n) = ((2*A156552(n))<A323243(n));
%Y Cf. A156552, A294937, A323243, A323244, A324732.
%K nonn
%O 1
%A _Antti Karttunen_, Mar 12 2019