A359162 a(n) = 1 if n is a number of the form 4u+3 with an even number of prime factors (counted with multiplicity), otherwise 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, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 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, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 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) = A065043(n) * A121262(1+n).

a(n) = A353557(n) - A359160(n).

a(n) = A121262(1+n) - A359152(n).

a(n) >= A353479(n).

Example

135 = 3 * 3 * 3 * 5 has an even number of prime factors and is of the form 4u+3, therefore a(135) = 1.

Prog

(PARI) A359162(n) = (!(bigomega(n)%2)&&(3==(n%4)));

Crossrefs

Characteristic function of A359163.

Cf. A065043, A121262, A353557, A359152, A359160.

Differs from A353479 for the first time at n=135, where a(135) = 1, while A353479(135) = 0.

Sequence in context: A296213 A353479 A360111 * A327932 A373979 A359546

Adjacent sequences: A359159 A359160 A359161 * A359163 A359164 A359165

Keyword

nonn

Author

Antti Karttunen, Dec 17 2022

Status

approved