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A359767 Numbers k such that A065043(k) = 1 but A359764(k) = 0, where A359764 is the parity of Dirichlet inverse of the former (which is the characteristic function of the numbers with an even number of prime factors). 6

%I #8 Jan 13 2023 16:25:43

%S 16,36,64,81,96,100,160,196,216,224,225,240,256,336,352,360,384,416,

%T 441,484,486,504,528,540,544,560,576,600,608,624,625,640,676,729,736,

%U 756,792,810,816,880,896,900,912,928,936,960,992,1000,1024,1040,1089,1104,1134,1156,1176,1184,1188,1215,1224,1225

%N Numbers k such that A065043(k) = 1 but A359764(k) = 0, where A359764 is the parity of Dirichlet inverse of the former (which is the characteristic function of the numbers with an even number of prime factors).

%o (PARI)

%o A065043(n) = (1 - (bigomega(n)%2));

%o memoA359763 = Map();

%o A359763(n) = if(1==n,1,my(v); if(mapisdefined(memoA359763,n,&v), v, v = -sumdiv(n,d,if(d<n,A065043(n/d)*A359763(d),0)); mapput(memoA359763,n,v); (v)));

%o A359764(n) = (A359763(n)%2);

%o isA359767(n) = (A065043(n)&&!(A359764(n)));

%Y Cf. A065043, A359763, A359764, A359765.

%Y Cf. also A359784.

%Y Setwise difference A028260 \ A359765.

%Y Setwise difference A359766 \ A026424.

%Y Subsequence of A013929.

%K nonn

%O 1,1

%A _Antti Karttunen_, Jan 13 2023

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Last modified August 18 23:05 EDT 2024. Contains 375284 sequences. (Running on oeis4.)