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A067118 a(n) =floor[X/Y] where X= concatenation of first n even numbers in decreasing order and Y = that of first n odd numbers in increasing order.

%I A067118 #10 Dec 05 2013 19:55:07
%S A067118 2,3,4,6,8,8,10,11,13,14,16,17,19,20,22,23,25,26,28,29,31,32,34,35,37,
%T A067118 38,40,41,43,44,46,47,49,50,52,53,55,56,58,59,60,62,63,65,66,68,69,71,
%U A067118 72,74,75,76,78,79,81,82,84,85,86,88,89,91,92,94,95,97,98,100,101,103
%N A067118 a(n) =floor[X/Y] where X= concatenation of first n even numbers in decreasing order and Y = that of first n odd numbers in increasing order.
%e A067118 a(4) = floor[8642/1357] = floor[6.368...] = 6.
%p A067118 for i from 1 to 50 do c := 2:n := 4:m := 2*i-1:d := m:m := m-2:while(m>0) do g := floor(log(c+1)/log(10)):c := c+10^(g)*n:n := n+2:g := floor(log(d)/log(10)): d := d+10^(g+1)*m:m := m-2:end do:a[i] := floor(c/d):end do:q := seq(a[j],j=1..50);
%t A067118 Table[Floor[FromDigits[Flatten[IntegerDigits/@Range[2n,2,-2]]]/FromDigits[ Flatten[IntegerDigits/@Range[1,2n-1,2]]]],{n,80}] (* _Harvey P. Dale_, Nov 02 2013 *)
%Y A067118 Cf. A067112-A067117.
%K A067118 easy,nonn,base
%O A067118 1,1
%A A067118 _Amarnath Murthy_, Jan 08 2002
%E A067118 More terms from _Sascha Kurz_, Mar 23 2002
%E A067118 Edited by _Charles R Greathouse IV_, Apr 27 2010