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Parity of A353348, where A353348 is Dirichlet inverse of the characteristic function for numbers k such that A048675(k) is a multiple of 3.
4

%I #16 Jan 24 2023 12:34:57

%S 1,0,0,0,0,1,0,1,0,0,0,0,0,1,1,0,0,0,0,1,0,0,0,0,0,1,1,0,0,0,0,0,1,0,

%T 1,0,0,1,0,0,0,0,0,1,0,0,0,1,0,1,1,0,0,0,0,0,0,1,0,0,0,0,1,0,1,0,0,1,

%U 1,0,0,0,0,1,0,0,1,0,0,0,0,0,0,1,0,1,0,0,0,1,0,1,1,0,1,0,0,0,0,0,0,0,0,0,0,1,0,0,0,1,0,1,0,0,0,0,1,0,1,1

%N Parity of A353348, where A353348 is Dirichlet inverse of the characteristic function for numbers k such that A048675(k) is a multiple of 3.

%H Antti Karttunen, <a href="/A359826/b359826.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) = A353348(n) mod 2.

%F a(n) = a(A003961(n)) = a(A348717(n)), for all n >= 1.

%F a(n) <= A353350(n). [Follows because A332820 is a multiplicative semigroup. See comments in A353348]

%o (PARI) A359826(n) = (A353348(n)%2);

%Y Characteristic function of A359827.

%Y Cf. A003961, A048675, A332820, A353348, A353350.

%Y Cf. also A359836.

%K nonn

%O 1

%A _Antti Karttunen_, Jan 17 2023