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%I #13 Sep 16 2019 08:50:50
%S 8,12,18,20,27,28,32,36,44,45,48,50,52,63,64,68,75,76,80,92,98,99,100,
%T 112,116,117,120,124,125,144,147,148,153,162,164,168,171,172,175,176,
%U 188,196,207,208,212,216,225,236,242,243,244,245,261,264,268,270,272
%N Numbers with mu = 0 and infinitary MoebiusMu = +1 (sum of binary digits of prime exponents is even).
%H Amiram Eldar, <a href="/A066428/b066428.txt">Table of n, a(n) for n = 1..10000</a>
%e 28 is in this sequence because its prime decomposition is 2^2* 7^1, it is not squarefree and the binary digits of "2" and "1" add up to 2, an even number.
%t iMoebiusMu[ n_ ] := Switch[ MoebiusMu[ n ], 1, 1, -1, -1, 0, If[ OddQ[ Plus@@(DigitCount[ Last[ Transpose[ FactorInteger[ n ] ]], 2, 1 ]) ], -1, 1 ]]; Select[ Range[ 400 ], MoebiusMu[ # ]===0 && iMoebiusMu[ # ]===+1 & ]
%o (PARI) is(n)=my(f=factor(n)[,2]); #f && vecmax(f)>1 && vecsum(apply(hammingweight, f))%2==0 \\ _Charles R Greathouse IV_, Oct 15 2015
%Y Cf. A064179, A066427.
%K easy,nonn
%O 1,1
%A _Wouter Meeussen_, Dec 27 2001
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