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A359820
a(n) = 1 if n and n' are of different parity, otherwise 0. Here n' stands for the arithmetic derivative of n, A003415(n).
7
0, 1, 1, 0, 0, 0, 1, 0, 0, 1, 1, 0, 0, 0, 1, 1, 0, 0, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 0, 1, 0, 0, 1, 1, 1, 0, 0, 1, 1, 0, 0, 1, 0, 0, 0, 1, 0, 0, 1, 1, 1, 0, 0, 1, 1, 0, 1, 1, 0, 0, 0, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 0, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 1, 0, 0, 1, 1, 0, 1, 1, 1, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 1
OFFSET
0
FORMULA
a(n) = A000035(A129283(n)).
PROG
(PARI)
A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
A359820(n) = ((n+A003415(n))%2);
CROSSREFS
Characteristic function of A359821, whose complement A359822 gives the positions of 0's.
Parity of A129283 and of A168036.
Cf. A000035, A003415, A359823 (Dirichlet inverse), A359824 (and its parity).
Cf. also A347871.
Sequence in context: A071981 A280910 A305816 * A241979 A200244 A261185
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jan 14 2023
STATUS
approved