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%I #11 Jul 17 2021 06:52:38
%S 50,75,100,125,150,175,190,200,222,225,238,242,246,250,275,285,300,
%T 325,333,338,350,357,363,369,374,375,380,400,425,438,442,444,450,475,
%U 476,484,492,494,500,507,525,550,555,561,570,575,578,595,600,605,615,625
%N Numbers k such that A294902(k) != A321516(k).
%t A321516[n_] := Length[Select[Most[Divisors[n]], CompositeQ]]; abQ[n_] := DivisorSum[n, Total[IntegerDigits[#, 2]]*(-1)^Boole[#==n]&]>0; A294902[n_] := Length[Select[Most[Divisors[n]], abQ[#] &]]; Select[Range[650], A321516[#] != A294902 [#] &] (* _Amiram Eldar_, Nov 12 2018 after _Jean-François Alcover_ at A175526 *)
%o (PARI) a292257(n) = sumdiv(n, d, (d<n)*hammingweight(d)) \\ after _Antti Karttunen_ in A292257
%o a294905(n) = (a292257(n) <= hammingweight(n)) \\ after _Antti Karttunen_ in A294905
%o a294902(n) = sumdiv(n, d, (d<n)*(0==a294905(d))) \\ after _Antti Karttunen_ in A294902
%o a321516(n) = my(d=divisors(n), i=0); for(k=2, #d-1, if(!ispseudoprime(d[k]), i++)); i
%o is(n) = a294902(n)!=a321516(n)
%Y Cf. A033942, A294902, A321516.
%K nonn
%O 1,1
%A _Felix Fröhlich_, Nov 12 2018
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