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A328590
a(n) = A328578(n) - A257993(n).
7
0, 1, 0, 2, 0, 0, 0, 2, 0, 3, 0, -1, 0, 3, 0, 2, 0, 0, 0, 4, 0, 4, 0, -1, 0, 4, 0, 5, 0, -2, 0, 2, 0, 1, 0, 0, 0, 3, 0, 4, 0, -1, 0, 4, 0, 4, 0, 0, 0, 5, 0, 5, 0, -1, 0, 5, 0, 3, 0, -2, 0, 3, 0, 2, 0, 0, 0, 4, 0, 4, 0, -1, 0, 5, 0, 5, 0, 0, 0, 5, 0, 6, 0, -1, 0, 4, 0, 6, 0, -2, 0, 4, 0, 5, 0, 0, 0, 5, 0, 5, 0, -1, 0, 5, 0
OFFSET
1,4
FORMULA
a(n) = A328578(n) - A257993(n).
PROG
(PARI)
A257993(n) = { for(i=1, oo, if(n%prime(i), return(i))); }
A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
A328590(n) = (A328578(n) - A257993(n));
CROSSREFS
Cf. A257993, A276086, A328578, A328585 (positions of zeros), A328587 (of negative terms), A328588 (of positive terms).
Cf. A328591 (even bisection).
Sequence in context: A361250 A165619 A368118 * A219204 A338264 A353509
KEYWORD
sign
AUTHOR
Antti Karttunen, Oct 21 2019
STATUS
approved