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Number of divisors d of n such that d is a multiple of its prime shadow A181819(d).
2

%I #7 Apr 29 2022 15:55:43

%S 1,2,1,2,1,2,1,2,2,2,1,3,1,2,1,2,1,4,1,2,1,2,1,3,1,2,2,2,1,2,1,2,1,2,

%T 1,6,1,2,1,3,1,2,1,2,2,2,1,3,1,2,1,2,1,4,1,2,1,2,1,4,1,2,2,2,1,2,1,2,

%U 1,2,1,6,1,2,1,2,1,2,1,3,2,2,1,4,1,2,1,2,1,4,1,2,1,2,1,3,1,2,2,2,1,2,1,2,1,2,1,6

%N Number of divisors d of n such that d is a multiple of its prime shadow A181819(d).

%C Number of terms of A325755 that divide n.

%H Antti Karttunen, <a href="/A353567/b353567.txt">Table of n, a(n) for n = 1..65537</a>

%F a(n) = Sum_{d|n} A353566(d).

%o (PARI)

%o A353566(n) = (0==(n%factorback(apply(e->prime(e),(factor(n)[,2])))));

%o A353567(n) = sumdiv(n,d,A353566(d));

%Y Inverse Möbius transform of A353566.

%Y Cf. A181819, A325755.

%K nonn

%O 1,2

%A _Antti Karttunen_, Apr 29 2022