A373253 a(n) is -1, 0, or 1 such that a(n) == A003415(n) (mod 3), where A003415 is the arithmetic derivative.

0, 0, 1, 1, 1, 1, -1, 1, 0, 0, 1, 1, 1, 1, 0, -1, -1, 1, 0, 1, 0, 1, 1, 1, -1, 1, 0, 0, -1, 1, 1, 1, -1, -1, 1, 0, 0, 1, 0, 1, -1, 1, -1, 1, 0, 0, 1, 1, 1, -1, 0, -1, -1, 1, 0, 1, -1, 1, 1, 1, -1, 1, 0, 0, 0, 0, 1, 1, 0, -1, -1, 1, 0, 1, 0, 1, -1, 0, -1, 1, -1, 0, 1, 1, 1, 1, 0, -1, -1, 1, 0, -1, 0, 1, 1, 0, -1, 1, -1, 0, -1

Offset

0

Links

Antti Karttunen, Table of n, a(n) for n = 0..65537

Prog

(PARI)
A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
A373253(n) = { my(u=A003415(n)%3); if(2==u, -1, u); };

Crossrefs

Cf. A003415, A327863 (positions of 0's), A373255 (positions of +1's), A373257 (positions of -1's).

Cf. also A332823, A373153.

Sequence in context: A295306 A295303 A288226 * A377988 A104121 A179770

Adjacent sequences: A373250 A373251 A373252 * A373254 A373255 A373256

Keyword

sign

Author

Antti Karttunen, May 31 2024

Status

approved