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%I #11 Dec 30 2022 16:14:47
%S 1,0,0,0,0,1,0,0,1,1,0,0,0,1,1,0,0,0,0,0,1,1,0,0,1,1,0,0,0,0,0,0,1,1,
%T 1,0,0,1,1,0,0,0,0,0,0,1,0,0,1,0,1,0,0,1,1,0,1,1,0,0,0,1,0,0,1,0,0,0,
%U 1,0,0,0,0,1,0,0,1,0,0,0,1,1,0,0,1,1,1,0,0,1,1,0,1,1,1,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,1,0,0,0,1,0,0,1,1,0,1
%N a(n) = 1 if n is not a multiple of 4 and has an even number of prime factors (with multiplicity), otherwise a(n) = 0.
%H Antti Karttunen, <a href="/A359370/b359370.txt">Table of n, a(n) for n = 1..100000</a>
%H <a href="/index/Ch#char_fns">Index entries for characteristic functions</a>
%F a(n) = A166486(n) - A359372(n).
%F a(n) = [A358839(n) > 0], where [ ] is the Iverson bracket.
%o (PARI) A359370(n) = ((n%4)&&!(bigomega(n)%2));
%Y Characteristic function of A359371.
%Y Cf. A001222, A166486, A358839, A359372.
%Y Cf. also A359170.
%K nonn
%O 1
%A _Antti Karttunen_, Dec 28 2022