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Parity of A360121, where A360121 is Dirichlet convolution of A342001 with A342002.
5

%I #11 Feb 20 2023 07:53:00

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

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

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

%N Parity of A360121, where A360121 is Dirichlet convolution of A342001 with A342002.

%H Antti Karttunen, <a href="/A360122/b360122.txt">Table of n, a(n) for n = 1..30030</a>

%H <a href="/index/Ch#char_fns">Index entries for characteristic functions</a>

%H <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a>

%F a(n) = A000035(A360121(n)).

%F Apparently, a(n) >= A360123(n) for all n. [See A360124 for the positions of differences]

%o (PARI) A360122(n) = (A360121(n)%2);

%Y Cf. A000035, A342001, A342002, A360121, A360124.

%Y Cf. also A360123, A360125.

%K nonn

%O 1

%A _Antti Karttunen_, Feb 19 2023