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A276467 a(n) = denominator of Sum_{d|n} 0.d.

%I A276467 #32 Sep 08 2022 08:46:17
%S A276467 10,10,5,10,5,5,5,2,10,10,100,25,100,50,20,50,100,25,100,2,100,100,
%T A276467 100,25,20,100,100,50,100,4,100,50,25,100,20,25,100,100,25,10,100,100,
%U A276467 100,100,5,100,100,5,100,20,25,100,100,100,50,50,25,100,100,100
%N A276467 a(n) = denominator of Sum_{d|n} 0.d.
%C A276467 Here 0.d means the decimal fraction obtained by writing d after the decimal point, e.g., 0.12 = 12/100 = 3/25.
%C A276467 The first few values of Sum_{d|n} 0.d for n=1,2,.. are: 1/10, 3/10, 2/5, 7/10, 3/5, 6/5, 4/5, 3/2, 13/10, 9/10, 21/100, 43/25, ...
%C A276467 a(16450) = 1: 16450 is the only integer < 5*10^7 such that Sum_{d|n} 0.d is an integer; Sum_{d|16450} 0.d = 0.1 + 0.2 + 0.5 + 0.7 + 0.10 + 0.14 + 0.25 + 0.35 + 0.47 + 0.50 + 0.70 + 0.94 + 0.175 + 0.235 + 0.329 + 0.350 + 0.470 + 0.658 + 0.1175 + 0.1645 + 0.2350 + 0.3290 + 0.8225 + 0.16450 = 9; see A276465.
%C A276467 No other term like 16450 up to 10^9. - _Michel Marcus_, Mar 30 2019
%C A276467 No other term like 16450 up to 4*10^11. - _Giovanni Resta_, Apr 03 2019
%F A276467 a(n) = A276466(n) / (Sum_{d|n} 0.d).
%e A276467 For n=12: Sum_{d|12} 0.d = 0.1 + 0.2 + 0.3 + 0.4 + 0.6 + 0.12 = 1.72 = 172/100 = 43/25; a(12) = 25.
%t A276467 Table[Denominator@ Total@ (#*1/10^(1 + Floor@ Log10@ #)) &@ Divisors@ n, {n, 60}] (* _Michael De Vlieger_, Sep 06 2016 *)
%o A276467 (Magma) [Denominator(&+[d / (10^(#Intseq(d))): d in Divisors(n)]): n in [1..1000]]
%o A276467 (PARI) a(n) = denominator(sumdiv(n, d, d/10^(#Str(d)))); \\ _Michel Marcus_, Sep 05 2016
%Y A276467 Cf. A276465, A276466 (numerators).
%Y A276467 Cf. A078267 and A078268 (both for 0.d).
%K A276467 base,nonn
%O A276467 1,1
%A A276467 _Jaroslav Krizek_, Sep 05 2016