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%I #8 Apr 09 2014 10:14:40
%S 1,2,6,12,12,4,28,56,504,2520,27720,27720,27720,27720,5544,11088,
%T 188496,62832,1193808,5969040,1989680,1989680,45762640,137287920,
%U 686439600,8923714800,80313433200,80313433200,2329089562800,2329089562800
%N a(n) = denominator of the sum of reciprocals of those positive integers which are <= n and are not among the first (n-1) terms of A130502.
%H Diana Mecum, <a href="/A130503/b130503.txt">Table of n, a(n) for n = 1..200</a>
%e The positive integers which are <= 9 and are missing from the first 8 terms of the (numerator) sequence A130502 are 2,3,4,6,7,8,9. So a(9) is the denominator of (1/2 +1/3 +1/4 +1/6 +1/7 +1/8 + 1/9 = 821/504).
%Y Cf. A130502.
%K frac,nonn
%O 1,2
%A _Leroy Quet_, May 31 2007
%E More terms from _Diana L. Mecum_, Jun 14 2007