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%I #11 Nov 03 2022 04:29:01
%S 1,0,0,0,0,1,0,0,0,1,0,0,0,1,0,0,0,0,0,0,0,1,0,0,0,1,0,0,0,0,0,0,0,1,
%T 0,1,0,1,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,1,0,1,0,1,0,0,0,0,0,0,
%U 0,0,0,0,0,1,0,0,0,0,0,0,0,1,0,1,0,1,0,0,0,0,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,1
%N a(n) = 1 if A001222(n) == 2*A007814(n), and otherwise 0, where A001222 is bigomega (number of prime factors with multiplicity) and A007814 is the 2-adic valuation of n.
%H Antti Karttunen, <a href="/A356170/b356170.txt">Table of n, a(n) for n = 1..100000</a>
%H <a href="/index/Ch#char_fns">Index entries for characteristic functions</a>
%t Array[Boole[PrimeOmega[#] == 2 IntegerExponent[#, 2]] &, 122] (* _Michael De Vlieger_, Nov 02 2022 *)
%o (PARI) A356170(n) = (bigomega(n) == 2*valuation(n,2));
%Y Characteristic function of A072978.
%Y Cf. A001222, A007814.
%K nonn
%O 1
%A _Antti Karttunen_, Nov 02 2022