A369006 - OEIS

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A369006

a(n) = 1 if there is no prime p such that p^p divides n' / gcd(n,n'), and 0 otherwise, where n' stands for the arithmetic derivative of n, A003415(n).

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

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OFFSET

COMMENTS

Question: Is there a formula for the asymptotic mean, which seems to be around 0.813...? Consider A369004 and A369007.

LINKS

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

Index entries for characteristic functions

FORMULA

a(1) = 0, for n > 1, a(n) = A359550(A083345(n)).

A368914(n) <= a(n) <= 1 - A369004(n).

PROG

(PARI)