A353474 a(n) = 1 if n is a number of the form p^2 * q, where p and q are primes with p < q, otherwise 0.

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

Offset

1

Comments

a(n) = 1 if n is not a cube of prime and A052126(n) is a square of prime, otherwise 0.

Links

Antti Karttunen, Table of n, a(n) for n = 1..65537

Index entries for characteristic functions

Formula

a(n) = A143731(n) * A302048(A052126(n)).

a(n) = A353472(n) - A353473(n).

Prog

(PARI)
A052126(n) = if(1==n, n, (n/vecmax(factor(n)[, 1])));
A353474(n) = (!isprimepower(n) && 2==isprimepower(A052126(n)));

Crossrefs

Characteristic function of A096156.

Cf. A010055, A052126, A143731, A302048, A353472, A353473.

Sequence in context: A354983 A179801 A374093 * A065202 A374100 A323547

Adjacent sequences: A353471 A353472 A353473 * A353475 A353476 A353477

Keyword

nonn

Author

Antti Karttunen, Apr 21 2022

Status

approved