login
A378436
Inverse Möbius transform of A033630, where A033630 is the number of partitions of n into distinct divisors of n.
2
1, 2, 2, 3, 2, 5, 2, 4, 3, 4, 2, 9, 2, 4, 4, 5, 2, 9, 2, 7, 4, 4, 2, 16, 3, 4, 4, 7, 2, 12, 2, 6, 4, 4, 4, 21, 2, 4, 4, 12, 2, 11, 2, 6, 6, 4, 2, 28, 3, 6, 4, 6, 2, 14, 4, 11, 4, 4, 2, 53, 2, 4, 6, 7, 4, 11, 2, 6, 4, 8, 2, 60, 2, 4, 6, 6, 4, 10, 2, 20, 5, 4, 2, 43, 4, 4, 4, 9, 2, 41, 4, 6, 4, 4, 4, 51, 2, 6, 6, 12
OFFSET
1,2
COMMENTS
The odd bisection differs from A099774 (the odd bisection of A000005) apparently in the positions given by A005231 (odd abundant numbers): 945, 1575, 2205, 2835, 3465, ...
LINKS
FORMULA
a(n) = Sum_{d|n} A033630(d).
PROG
(PARI)
A033630(n) = if(!n, 1, my(p=1); fordiv(n, d, p *= (1 + 'x^d)); polcoeff(p, n));
A378436(n) = sumdiv(n, d, A033630(d));
CROSSREFS
Cf. A000005, A005231, A033630, A099774, A378438 (Dirichlet inverse).
Sequence in context: A141822 A033099 A330833 * A337331 A018892 A343654
KEYWORD
nonn
AUTHOR
Antti Karttunen, Nov 26 2024
STATUS
approved