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%I #16 Jun 06 2020 10:45:17
%S 1,3,6,6,7,8,9,10,9,12,12,15,14,12,14,13,18,19,18,15,18,15,20,14,24,
%T 21,18,21,24,18,24,21,27,33,30,28,28,32,36,30,21,26,27,24,27,38,30,36,
%U 35,45,36,42,39,26,44,28,40,51,30,36,28,48,54,42,45,38,31,39,36,48,60,54
%N a(n) = sigma(A023883(n)) / tau(A023883(n)).
%C Arithmetic means of divisors of nonprime arithmetic numbers (A023883). - _Amiram Eldar_, Jun 06 2020
%H Amiram Eldar, <a href="/A072910/b072910.txt">Table of n, a(n) for n = 1..10000</a>
%t meanDiv[n_] := DivisorSigma[1, n]/DivisorSigma[0, n]; Select[meanDiv /@ Select[Range[200], !PrimeQ[#] &], IntegerQ] (* _Amiram Eldar_, Jun 06 2020 *)
%o (PARI) f(x) = sigma(x)/numdiv(x);
%o apply(x->f(x), select(x->((denominator(f(x))==1) && !isprime(x)), [1..1000])) \\ _Michel Marcus_, Jun 06 2020
%Y Cf. A000005, A000203, A003601, A102187, A023883.
%K easy,nonn
%O 1,2
%A _Benoit Cloitre_, Aug 10 2002
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