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A324830
Number of divisors d of n such that A323243(d) is a multiple of 3.
6
1, 1, 2, 1, 1, 3, 2, 1, 3, 1, 1, 4, 2, 3, 3, 2, 1, 4, 2, 1, 4, 2, 1, 5, 1, 3, 4, 4, 2, 4, 1, 2, 3, 1, 3, 5, 2, 3, 4, 1, 1, 6, 2, 2, 5, 1, 1, 7, 3, 1, 3, 4, 2, 6, 1, 5, 4, 3, 1, 5, 2, 2, 6, 2, 3, 6, 1, 1, 3, 5, 2, 7, 1, 3, 4, 4, 3, 6, 2, 2, 5, 1, 1, 8, 2, 3, 4, 3, 2, 7, 4, 1, 3, 2, 3, 8, 1, 5, 5, 2, 2, 5, 1, 5, 7
OFFSET
1,3
FORMULA
a(n) = A000005(n) - (A324831(n) + A324832(n)).
For all n >= 1, a(A000040(n)) = 2-A000035(n).
PROG
(PARI) A324830(n) = sumdiv(n, d, (0==(A323243(d))%3));
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 16 2019
STATUS
approved