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A351945 a(n) = A342001(A181819(n)).

%I A351945 #9 Apr 03 2022 13:53:44
%S A351945 0,1,1,1,1,2,1,1,1,2,1,5,1,2,2,1,1,5,1,5,2,2,1,7,1,2,1,5,1,3,1,1,2,2,
%T A351945 2,2,1,2,2,7,1,3,1,5,5,2,1,9,1,5,2,5,1,7,2,7,2,2,1,8,1,2,5,1,2,3,1,5,
%U A351945 2,3,1,8,1,2,5,5,2,3,1,9,1,2,1,8,2,2,2,7,1,8,2,5,2,2,2,13,1,5,5,2,1,3,1,7,3
%N A351945 a(n) = A342001(A181819(n)).
%H A351945 Antti Karttunen, <a href="/A351945/b351945.txt">Table of n, a(n) for n = 1..20000</a>
%H A351945 <a href="/index/Eu#epf">Index entries for sequences computed from exponents in factorization of n</a>
%F A351945 a(n) = A342001(A181819(n)) = A351942(n) / A351944(n).
%o A351945 (PARI)
%o A351945 A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
%o A351945 A003557(n) = (n/factorback(factorint(n)[, 1]));
%o A351945 A181819(n) = factorback(apply(e->prime(e),(factor(n)[,2])));
%o A351945 A342001(n) = (A003415(n) / A003557(n));
%o A351945 A351945(n) = A342001(A181819(n));
%Y A351945 Cf. A003415, A003557, A181819, A342001, A351942, A351954 [= a(A276076(n))].
%K A351945 nonn
%O A351945 1,6
%A A351945 _Antti Karttunen_, Apr 02 2022