A324831 Number of divisors d of n such that A323243(d) == 1 (mod 3).

0, 1, 0, 2, 1, 1, 0, 2, 0, 3, 1, 2, 0, 1, 1, 2, 1, 1, 0, 4, 0, 2, 1, 2, 2, 1, 0, 2, 0, 3, 1, 2, 1, 2, 1, 3, 0, 1, 0, 4, 1, 1, 0, 3, 1, 2, 1, 2, 0, 5, 1, 2, 0, 1, 3, 2, 0, 1, 1, 4, 0, 2, 0, 2, 1, 2, 1, 4, 1, 3, 0, 3, 1, 1, 2, 2, 1, 2, 0, 4, 0, 2, 1, 3, 2, 1, 0, 3, 0, 3, 0, 4, 1, 2, 1, 2, 1, 1, 1, 6, 0, 2, 1, 2, 1

Offset

1,4

Links

Antti Karttunen, Table of n, a(n) for n = 1..10000 (based on Hans Havermann's factorization of A156552)

Index entries for sequences related to binary expansion of n

Index entries for sequences computed from indices in prime factorization

Index entries for sequences related to sigma(n)

Formula

a(n) = A000005(n) - (A324830(n) + A324832(n)).

For all n >= 1, a(A000040(n)) = A000035(n).

Prog

(PARI) A324831(n) = sumdiv(n, d, (1==(A323243(d))%3));

Crossrefs

Cf. A000005, A000203, A156552, A323243, A324830, A324832.

Sequence in context: A166712 A035183 A178101 * A054522 A110250 A065252

Adjacent sequences: A324828 A324829 A324830 * A324832 A324833 A324834

Keyword

nonn

Author

Antti Karttunen, Mar 16 2019

Status

approved