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 A110091 Denominators of sequence of rationals defined by r(n) = n for n<=1 and for n>1: r(n) = (sum of denominators of r(n-1) and r(n-2))/(sum of numerators of r(n-1) and r(n-2)). 1

%I

%S 1,1,1,3,1,3,5,1,5,7,1,7,9,1,9,11,1,11,13,1,13,15,1,15,17,1,17,19,1,

%T 19,21,1,21,23,1,23,25,1,25,27,1,27,29,1,29,31,1,31,33,1,33,35,1,35,

%U 37,1,37,39,1,39,41,1,41,43,1,43,45,1,45,47,1,47,49,1,49,51,1,51,53,1,53,55

%N Denominators of sequence of rationals defined by r(n) = n for n<=1 and for n>1: r(n) = (sum of denominators of r(n-1) and r(n-2))/(sum of numerators of r(n-1) and r(n-2)).

%C r(n) = A110090(n) / a(n);

%C a(n) = (A110090(n-1)+A110090(n-2)) / GCD(a(n-1)+a(n-2),A110090(n-1)+A110090(n-2)).

%F a(3*k) = 2*k+1, a(3*k+1) = 1, a(3*k+2) = 2*k+1.

%K nonn,frac

%O 0,4

%A _Reinhard Zumkeller_, Jul 14 2005

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Last modified June 14 05:51 EDT 2021. Contains 345018 sequences. (Running on oeis4.)