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A024835
a(n) = least m such that if r and s in {1/2, 1/4, 1/6, ..., 1/2n} satisfy r < s, then r < k/m < (k+1)/m < s for some integer k.
3
7, 17, 31, 49, 81, 111, 157, 197, 257, 307, 381, 441, 529, 625, 703, 813, 931, 1025, 1157, 1297, 1407, 1561, 1723, 1849, 2025, 2209, 2401, 2551, 2757, 2971, 3193, 3365, 3601, 3845, 4097, 4291, 4557, 4831, 5113, 5329, 5625, 5929, 6241, 6561, 6807, 7141, 7483, 7833
OFFSET
2,1
COMMENTS
For a guide to related sequences, see A001000. - Clark Kimberling, Aug 12 2012
LINKS
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]), #] &, Range[5]];
t[[2]] (* A024835 *)
(* Peter J. C. Moses, Aug 06 2012 *)
CROSSREFS
Sequence in context: A130284 A056220 A024840 * A225251 A178491 A319304
KEYWORD
nonn
STATUS
approved