%I
%S 2,2,3,4,54,6391,721719,73719014,819008271,900826453,982644636,
%T 1064462818,1146281001,1228099183,1309917366,1391735548,1473553731,
%U 1555371913,1637190096,1719008278,1800826461,1882644643,1964462826
%N Floor[X/Y] where X = concatenation of (n+1), (n+2), ...up to 2n and Y = concatenation of 1,2,3,4,... up to n.
%e a(4) =floor[ 5678/1234]= floor[4.60129659643435980551053484602917] = 4; a(6)= floor [ 789101112/123456] = 6391.
%t f[n_] := (k = 1; x = y = "0"; While[k < n + 1, x = StringJoin[x, ToString[n + k]]; y = StringJoin[y, ToString[2k  1]]; k++ ]; Return[ Floor[ ToExpression[x] / ToExpression[y]]] ); Table[ f[n], {n, 1, 24} ]
%K easy,base,nonn
%O 0,1
%A _Amarnath Murthy_, Jan 07 2002
%E More terms from _Robert G. Wilson v_, Jan 09 2002
