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A067121 a(n) = floor[X/Y] where X = the concatenation of the first n even numbers in increasing order and Y = their sum.

%I A067121 #12 Dec 05 2014 14:48:25
%S A067121 1,4,20,123,8227,587643,44073235,3427918353,274233468240,
%T A067121 22437283765107,1869773647092288,158211616292424373,
%U A067121 13560995682207803419,1175286292458009629726,102837550590075842601095
%N A067121 a(n) = floor[X/Y] where X = the concatenation of the first n even numbers in increasing order and Y = their sum.
%H A067121 Harvey P. Dale, <a href="/A067121/b067121.txt">Table of n, a(n) for n = 1..352</a>
%e A067121 a(4): floor[2468/(2+4+6+8)] = floor[123.4] = 123.
%p A067121 for i from 1 to 33 do n := 2*i:s := n:c := n:n := n-2:while(n>0) do s := s+n:g := floor(log(c+1)/log(10)):c := c+10^(g+1)*n:n := n-2:end do:a[i] := floor(c/s):end do:q := seq(a[j],j=1..33);
%t A067121 Module[{nn=20,ev},ev=2*Range[nn];Table[Floor[FromDigits[Flatten[ IntegerDigits/@ Take[ev,n]]]/(n^2+n)],{n,nn}]] (* _Harvey P. Dale_, Dec 05 2014 *)
%Y A067121 Cf. A067112-A067120.
%K A067121 easy,nonn,base
%O A067121 1,2
%A A067121 _Amarnath Murthy_, Jan 08 2002
%E A067121 More terms from _Sascha Kurz_, Mar 23 2002