login
Parity of A359780, where A359780 is the Dirichlet inverse of the characteristic function of the numbers with even arithmetic derivative (A003415).
8

%I #12 Jan 14 2023 18:36:36

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

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

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

%N Parity of A359780, where A359780 is the Dirichlet inverse of the characteristic function of the numbers with even arithmetic derivative (A003415).

%H Antti Karttunen, <a href="/A359781/b359781.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) = A359780(n) mod 2.

%F a(n) <= A358680(n). [See comments in A359780]

%F a(A056913(n)) = 1.

%o (PARI) A359781(n) = (A359780(n)%2);

%Y Parity of A359780 and of A359790.

%Y Characteristic function of A359783, whose complement is A359782.

%Y Cf. A056913, A358680, A359784 (where differs from A358680).

%Y Cf. also A359764 [= a(A003961(n)], A359774.

%K nonn

%O 1

%A _Antti Karttunen_, Jan 13 2023