A024847 a(n) = least m such that if r and s in {1/1, 1/3, 1/5, ..., 1/(2n-1)} satisfy r < s, then r < k/m < (k+4)/m < s for some integer k.

8, 34, 76, 134, 208, 298, 404, 526, 664, 818, 1009, 1198, 1427, 1651, 1918, 2176, 2481, 2773, 3116, 3442, 3823, 4183, 4602, 4996, 5453, 5881, 6376, 6838, 7371, 7867, 8438, 8969, 9578, 10207, 10791, 11458, 12145, 12781, 13506, 14251, 14939, 15722, 16525, 17265

Offset

2,1

Comments

For a guide to related sequences, see A001000. - Clark Kimberling, Aug 12 2012

Links

Clark Kimberling, Table of n, a(n) for n = 2..100

Mathematica

leastSeparatorS[seq_, s_] := Module[{n = 1},
Table[While[Or @@ (Ceiling[n #1[[1]]] <
s + 1 + Floor[n #1[[2]]] &) /@ (Sort[#1, Greater] &) /@
Partition[Take[seq, k], 2, 1], n++]; n, {k, 2, Length[seq]}]];
t = Map[leastSeparatorS[1/(2*Range[50]-1), #] &, Range[5]];
t[[5]] (* A024847 *)
(* Peter J. C. Moses, Aug 06 2012 *)

Crossrefs

Cf. A001000, A024848.

Sequence in context: A196143 A373356 A307091 * A154516 A212744 A298174

Adjacent sequences: A024844 A024845 A024846 * A024848 A024849 A024850

Keyword

nonn

Author

Clark Kimberling

Status

approved