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 A276651 a(n) = numerator of Sum_{p|n} 0.d where p runs through the prime divisors of n. 6

%I

%S 1,3,1,1,1,7,1,3,7,11,1,13,9,4,1,17,1,19,7,1,31,23,1,1,33,3,9,29,1,31,

%T 1,41,37,6,1,37,39,43,7,41,6,43,31,4,43,47,1,7,7,47,33,53,1,61,9,49,

%U 49,59,1,61,51,1,1,63,61,67,37,53,7,71,1,73,57,4,39

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

%C Here 0.d means the decimal fraction obtained by writing d after the decimal point, e.g., 0.11 = 11/100.

%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="/A276651/b276651.txt">Table of n, a(n) for n = 2..1000</a>

%F a(n) = (Sum_{p|n} 0.d) * A276652(n) 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) = 1.

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

%t Total[f*10^-IntegerLength[f]], {i, 2, 76}]] (* _Robert Price_, Sep 20 2019 *)

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

%Y Cf. A276652, A276653, A276654, A276655, A276513.

%K nonn,base,frac

%O 2,2

%A _Jaroslav Krizek_, Sep 10 2016

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Last modified October 15 01:40 EDT 2019. Contains 328025 sequences. (Running on oeis4.)