A345375 Number of unitary prime divisors of n whose prime index is even.

0, 0, 1, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 1, 0, 2, 0, 0, 1, 0, 1, 0, 1, 1, 1, 0, 0, 1, 0, 1, 0, 1, 1, 2, 0, 0, 2, 1, 0, 0, 0, 0, 1, 0, 0, 1, 1, 1, 0, 0, 1, 2, 1, 0, 1, 1, 0, 1, 0, 1, 1, 0, 0, 1, 1, 1, 0, 0, 1, 1, 1, 1, 2, 1, 0, 0, 0, 0, 2, 0, 1, 2, 0, 1, 0, 2, 0, 1

Offset

1,21

Links

Table of n, a(n) for n=1..93.

Formula

a(n) = Sum_{p|n, p prime} ((pi(p)+1) mod 2) * floor(1/gcd(p,n/p)).

Crossrefs

Cf. A056169.

Sequence in context: A025462 A024879 A024316 * A101669 A243067 A086965

Adjacent sequences: A345372 A345373 A345374 * A345376 A345377 A345378

Keyword

nonn

Author

Wesley Ivan Hurt, Jun 16 2021

Status

approved