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%I #10 Aug 16 2016 17:38:28
%S 10,10,5,1,2,10,5,5,2,5,100,100,25,10,4,100,50,25,20,20,25,50,100,20,
%T 10,25,100,100,5,10,100,100,50,1,20,100,25,50,20,4,50,25,100,20,5,50,
%U 100,100,10,5,100,100,25,10,20,100,50,25,4,20,25,50,100,20,2,25,100,100,5,10,100,100,50
%N Denominator of Sum_{k=1..n} 0.k.
%C Here 0.k means the decimal fraction obtained by writing k after the decimal point, e.g. 0.12 = 12/100 = 3/25.
%H Alois P. Heinz, <a href="/A275626/b275626.txt">Table of n, a(n) for n = 1..20000</a>
%e The first few values of Sum{k=1..n} 0.k are:
%e 1/10, 3/10, 3/5, 1, 3/2, 21/10, 14/5, 18/5, 9/2, 23/5, 471/100, 483/100, 124/25, 51/10, 21/4, 541/100, 279/50, 144/25, 119/20, 123/20, 159/25, 329/50, 681/100, 141/20, 73/10, 189/25, ...
%p b:= proc(n) option remember;
%p n/10^length(n)+`if`(n<2, 0, b(n-1))
%p end:
%p a:= n-> denom(b(n)):
%p seq(a(n), n=1..100); # _Alois P. Heinz_, Aug 16 2016
%Y Cf. A275626, A054464 (when a(n) = 1), A275623, A275624.
%K nonn,base,frac
%O 1,1
%A _N. J. A. Sloane_, Aug 07 2016
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