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a(n) = A051903(A003415(n)) - A051903(n).
10

%I #6 Oct 13 2019 18:09:37

%S -1,-1,0,-1,0,-1,-1,-1,0,-1,2,-1,1,2,1,-1,-1,-1,1,0,0,-1,-1,-1,0,0,3,

%T -1,0,-1,-1,0,0,1,0,-1,0,3,-1,-1,0,-1,2,-1,1,-1,0,-1,0,1,1,-1,1,3,-1,

%U 0,0,-1,0,-1,0,-1,0,1,0,-1,1,0,0,-1,-1,-1,0,-1,2,1,0,-1,0,-1,0,-1,0,0,1,4,-1,-1,-1,1,3,0,1,2

%N a(n) = A051903(A003415(n)) - A051903(n).

%H Antti Karttunen, <a href="/A328310/b328310.txt">Table of n, a(n) for n = 2..20000</a>

%F a(n) = A051903(A003415(n)) - A051903(n).

%F a(n) = A328311(n) - 1.

%o (PARI)

%o A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));

%o A051903(n) = if((1==n),0,vecmax(factor(n)[, 2]));

%o A328310(n) = (A051903(A003415(n)) - A051903(n));

%Y Cf. A003415, A051903, A328320, A328321.

%Y One less than A328311.

%K sign

%O 2,11

%A _Antti Karttunen_, Oct 13 2019