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A322584 Number of divisors of n that area product of primorial numbers (terms of A025487). 4

%I

%S 1,2,1,3,1,3,1,4,1,2,1,5,1,2,1,5,1,3,1,3,1,2,1,7,1,2,1,3,1,4,1,6,1,2,

%T 1,6,1,2,1,4,1,3,1,3,1,2,1,9,1,2,1,3,1,3,1,4,1,2,1,7,1,2,1,7,1,3,1,3,

%U 1,2,1,9,1,2,1,3,1,3,1,5,1,2,1,5,1,2,1,4,1,4,1,3,1,2,1,11,1,2,1,3,1,3,1,4,1

%N Number of divisors of n that area product of primorial numbers (terms of A025487).

%C a(n) is the number of terms of A025487 that divide n.

%H Antti Karttunen, <a href="/A322584/b322584.txt">Table of n, a(n) for n = 1..20000</a>

%H Antti Karttunen, <a href="/A322584/a322584.txt">Data supplement: n, a(n) computed for n = 1..100000</a>

%F a(n) = Sum_{d|} A322585(d).

%o (PARI)

%o A322585(n) = { my(f = factor(n)); for(i=1,#f~,if((primepi(f[i,1])!=i)||((i>1)&&(f[i-1,2]<f[i,2])),return(0))); (1); };

%o A322584(n) = sumdiv(n,d,A322585(d));

%Y Inverse Möbius transform of A322585.

%Y Cf. A025487.

%Y Cf. also A181801.

%K nonn

%O 1,2

%A _Antti Karttunen_, Dec 20 2018

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Last modified October 22 09:56 EDT 2019. Contains 328315 sequences. (Running on oeis4.)