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T. D. Noe and Alois P. Heinz, <a href="/A068311/b068311.txt">Table of n, a(n) for n = 0..450</a> (first 101 terms from T. D. Noe)
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(Python 3.8+)
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= (1*3 + 2*1)*4 + 6*(2*2*1) = 5*4 + 6*4 = 44;
where d(n) = A003415(n) with d(1)=0, d(prime)=1 and d(m*n)= d (m)*n + m*d(n).
a(6)=2064 because the arithmetic derivative of 6!=720 is 720*(4/2 + 2/3 + 1/5).
(MAGMAMagma) Ad:=func<h | h*(&+[Factorisation(h)[i][2]/Factorisation(h)[i][1]: i in [1..#Factorisation(h)]])>; [n le 1 select 0 else Ad(Factorial(n)): n in [0..30]]; // Bruno Berselli, Oct 23 2013
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