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%I #7 Jan 24 2024 18:32:38
%S 1,1,1,0,1,0,1,0,0,0,1,1,1,0,0,1,1,1,1,1,0,0,1,0,0,0,0,1,1,0,1,1,0,0,
%T 0,1,1,0,0,0,1,0,1,1,1,0,1,1,0,1,0,1,1,0,0,0,0,0,1,0,1,0,1,0,0,0,1,1,
%U 0,0,1,0,1,0,1,1,0,0,1,1,1,0,1,0,0,0,0,0,1,0,0,1,0,0,0,0,1,1,1,1,1,0,1,0,0,0,1,0,1,0,0,1,1,0,0,1,1,0,0,0,0,0,0,1,0
%N Parity of A038548, where A038548(n) is the number of divisors of n that are at most sqrt(n).
%C Also parity of the Möbius transform of A369255.
%H Antti Karttunen, <a href="/A369253/b369253.txt">Table of n, a(n) for n = 1..65537</a>
%H <a href="/index/Ch#char_fns">Index entries for characteristic functions</a>
%F a(n) = A000035(A038548(n)).
%o (PARI) A369253(n) = (sumdiv(n,d,1-(bigomega(d)%2))%2);
%Y Characteristic function of A369254.
%Y Cf. A000035, A065043, A038548, A369255.
%K nonn
%O 1
%A _Antti Karttunen_, Jan 24 2024