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Fully additive with a(n) = n-1 for n <= 3, and a(p) = 1 + a(A048673(p)) when p is prime > 3 and a(n*m) = a(n) + a(m) when m,n > 1.
5

%I #9 May 13 2020 18:59:14

%S 0,1,2,2,3,3,4,3,4,4,5,4,5,5,5,4,5,5,5,5,6,6,6,5,6,6,6,6,5,6,6,5,7,6,

%T 7,6,7,6,7,6,7,7,6,7,7,7,7,6,8,7,7,7,7,7,8,7,7,6,7,7,7,7,8,6,8,8,7,7,

%U 8,8,8,7,7,8,8,7,9,8,8,7,8,8,8,8,8,7,7,8,9,8,9,8,8,8,8,7,8,9,9,8,8,8,8,8,9

%N Fully additive with a(n) = n-1 for n <= 3, and a(p) = 1 + a(A048673(p)) when p is prime > 3 and a(n*m) = a(n) + a(m) when m,n > 1.

%H Antti Karttunen, <a href="/A334200/b334200.txt">Table of n, a(n) for n = 1..65537</a>

%H <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>

%o (PARI) A334200(n) = if(n<=3, n-1, if(isprime(n), 1+A334200((1+nextprime(1+n))/2), my(f=factor(n)); (apply(A334200, f[, 1])~ * f[, 2])));

%Y Cf. A048673, A334199.

%Y Cf. also A064097, A334206.

%K nonn

%O 1,3

%A _Antti Karttunen_, May 13 2020