A359835 - OEIS

%I #8 Jan 25 2023 17:29:30

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

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

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

%N a(n) = 0 if A353418(n) = 0, otherwise 1. Here A353418 is Dirichlet inverse of the characteristic function for numbers k at which points A156552(k) is a multiple of 3.

%C In contrast to A359836, which seems to satisfy A359836(n) <= A353269(n), here a(n) - A353269(n) may obtain any of the values -1, 0 or +1.

%H Antti Karttunen, <a href="/A359835/b359835.txt">Table of n, a(n) for n = 1..100000</a>

%H <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>

%F a(n) = [A353418(n) != 0], where [ ] is the Iverson bracket.

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

%F a(n) >= A359836(n).

%o (PARI) A359835(n) = !!A353418(n);

%Y Characteristic function for nonzero terms of A353418.

%Y Cf. A156552, A353269, A359836.

%K nonn

%O 1

%A _Antti Karttunen_, Jan 21 2023