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.

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, 38, 40, 41, 43, 44, 46, 47, 49, 50, 52, 53, 55, 56, 58, 59, 60, 62, 63, 65, 66, 68, 69, 71, 72, 74, 75, 76, 78, 79, 81, 82, 84, 85, 86, 88, 89, 91, 92, 94, 95, 97, 98, 100, 101, 103

Offset: 1

Author

Amarnath Murthy, Jan 08 2002

Keywords

• easy
• nonn
• base

Examples

			a(4) = floor[8642/1357] = floor[6.368...] = 6.
		

Crossrefs

Cf. A067112-A067117.

Programs

Maple

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);

Mathematica

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 *)

Extensions

More terms from Sascha Kurz, Mar 23 2002

Edited by Charles R Greathouse IV, Apr 27 2010