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%I #6 Oct 01 2012 16:21:04
%S 1,5,10,77,26,223,988,3909,748,55991,5084,785633,124658,207061,
%T 1096792,29889983,1893246,197698279,85352744,154834887,47589202,
%U 325333835,1188897016,7612795845,5775510652,183259245573,33778670612
%N Numerators of row sums of array of rationals A038566(n)/A020653(n), n>=2.
%C Denominators are given by A069220.
%C See the W. Lang link under A038566 for the rationals and more.
%F a(n)=numerator(sum(r(n, k), k=1..phi(n))), with phi(n)=A000010(n) (Euler's totient function) and r(n, k):=A038566(n,k)/A020653(n,k), n>=2, if A020653 is read as an irregular triangle.
%e Rationals a(n)/A038566(n): [1, 5/2, 10/3, 77/12, 26/5, 223/20,
%e 988/105, 3909/280, 748/63, 55991/2520,...]
%K nonn,easy
%O 2,2
%A _Wolfdieter Lang_, Sep 12 2005
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