A369058 a(n) = 1 if n is a product of three (not necessarily distinct) odd primes, otherwise 0.

0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1

Offset

1

Links

Antti Karttunen, Table of n, a(n) for n = 1..100000

Index entries for characteristic functions

Formula

a(n) = A000035(n) * A101605(n).

Example

a(27) = 1 because 27 = 3*3*3.
a(45) = 1 because 45 = 3*3*5.

Prog

(PARI) A369058(n) = ((n%2)&&(3==bigomega(n)));

Crossrefs

Characteristic function of A046316.

Cf. A000035, A001222, A101605.

Sequence in context: A011743 A011742 A011741 * A277165 A011740 A354344

Adjacent sequences: A369055 A369056 A369057 * A369059 A369060 A369061

Keyword

nonn

Author

Antti Karttunen, Jan 20 2024

Status

approved