A368912 a(n) = 1 if A342001(n) is squarefree, and 0 otherwise.

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

Offset

1

Comments

Question: What is the asymptotic mean of this and related sequences like A354874 and A368914?

Links

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

Index entries for characteristic functions

Formula

a(1) = 0, and for n > 1, a(n) = A008966(A342001(n)).

For all n >= 1, A354874(n) <= a(n) <= A368914(n).

Prog

(PARI)
A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
A003557(n) = (n/factorback(factorint(n)[, 1]));
A342001(n) = (A003415(n) / A003557(n));
A368912(n) = ((n>1)&&issquarefree(A342001(n)));

Crossrefs

Characteristic function of A368902.

Cf. A003415, A008966, A342001, A354874, A368914.

Sequence in context: A168184 A013595 A339145 * A368914 A360122 A369006

Adjacent sequences: A368909 A368910 A368911 * A368913 A368914 A368915

Keyword

nonn

Author

Antti Karttunen, Jan 10 2024

Status

approved