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a(n) = denominator of Sum_{p|n} 0.d where p runs through the prime divisors of n.
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%I #13 Sep 08 2022 08:46:17

%S 5,10,5,2,2,10,5,10,10,100,2,100,10,5,5,100,2,100,10,1,100,100,2,2,

%T 100,10,10,100,1,100,5,100,100,5,2,100,100,100,10,100,5,100,100,5,100,

%U 100,2,10,10,100,100,100,2,100,10,100,100,100,1,100,100,1,5,100

%N a(n) = denominator of Sum_{p|n} 0.d where p runs through the prime divisors of n.

%C The first few values of Sum_{p|n} 0.d are: 1/5, 3/10, 1/5, 1/2, 1/2, 7/10, 1/5, 3/10, 7/10, ...

%C See A276655 - numbers n such that Sum_{p|n} 0.d is an integer.

%H Jaroslav Krizek, <a href="/A276652/b276652.txt">Table of n, a(n) for n = 2..1000</a>

%F a(n) = A276651(n) / (Sum_{p|n} 0.d) where p = prime divisors of n.

%e For n=12; Sum_{p|12} 0.d = 0.2 + 0.3 = 0.5 = 5/10 = 1/2; a(12) = 2.

%t Denominator[Table[f = FactorInteger[i][[All, 1]];

%t Total[f*10^-IntegerLength[f]], {i, 2, 65}]] (* _Robert Price_, Sep 20 2019 *)

%o (Magma) [Denominator(&+[d/(10^(#Intseq(d))): d in PrimeDivisors(n)]): n in [2..1000]]

%Y Cf. A276651, A276653, A276654, A276655, A276513.

%K nonn,base,frac

%O 2,1

%A _Jaroslav Krizek_, Sep 10 2016