A324826 Number of divisors d of n such that A323243(d) is either 0 or 1 (mod 4).

1, 2, 1, 3, 1, 2, 1, 4, 2, 3, 1, 4, 1, 2, 1, 5, 1, 3, 1, 5, 1, 3, 1, 6, 2, 3, 3, 4, 1, 4, 1, 6, 1, 3, 1, 6, 1, 2, 2, 7, 1, 2, 1, 5, 3, 3, 1, 8, 2, 4, 2, 5, 1, 4, 1, 6, 2, 2, 1, 8, 1, 3, 3, 7, 1, 4, 1, 5, 1, 3, 1, 9, 1, 3, 2, 4, 1, 5, 1, 9, 4, 3, 1, 6, 2, 3, 2, 7, 1, 6, 1, 5, 1, 3, 2, 10, 1, 4, 3, 7, 1, 4, 1, 7, 2

Offset

1,2

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) - A324827(n).

a(p) = 1 for all odd primes p.

Prog

(PARI) A324826(n) = sumdiv(n, d, ((A323243(d)%4)<2));

Crossrefs

Cf. A000005, A324825, A324827, A324830, A324831, A324832.

Sequence in context: A065704 A325565 A286552 * A277892 A214743 A331179

Adjacent sequences: A324823 A324824 A324825 * A324827 A324828 A324829

Keyword

nonn

Author

Antti Karttunen, Mar 16 2019

Status

approved