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Odd part of number of divisors of primorial inflation of n: a(n) = A000265(A329605(n)).
3

%I #10 Jan 14 2020 22:19:17

%S 1,1,1,3,1,3,1,1,9,3,1,1,1,3,9,5,1,3,1,1,9,3,1,5,27,3,1,1,1,3,1,3,9,3,

%T 27,15,1,3,9,5,1,3,1,1,1,3,1,3,81,9,9,1,1,5,27,5,9,3,1,15,1,3,1,7,27,

%U 3,1,1,9,9,1,9,1,3,3,1,81,3,1,3,25,3,1,15,27,3,9,5,1,5,81,1,9,3,27,7,1,27,1,45,1,3,1,5,3

%N Odd part of number of divisors of primorial inflation of n: a(n) = A000265(A329605(n)).

%H Antti Karttunen, <a href="/A331286/b331286.txt">Table of n, a(n) for n = 1..10000</a>

%H Antti Karttunen, <a href="/A331286/a331286.txt">Data supplement: n, a(n) computed for n = 1..65537</a>

%F a(n) = A000265(A329605(n)).

%F a(n) = A212181(A108951(n)).

%o (PARI) A331286(n) = if(1==n,1,my(f=factor(n),e=1,m=1); forstep(i=#f~,1,-1, e += f[i,2]; m *= (e>>valuation(e,2))^(primepi(f[i,1])-if(1==i,0,primepi(f[i-1,1])))); (m));

%Y Cf. A000265, A108951, A212181, A329605.

%Y Cf. also A322865.

%K nonn

%O 1,4

%A _Antti Karttunen_, Jan 14 2020