A246406 - OEIS

A246406

Nonnegative integers k satisfying sec(k) > sec(k+1) > sec(k+2) < sec(k+3).

11, 55, 99, 143, 210, 254, 298, 342, 388, 432, 476, 520, 543, 587, 631, 675, 721, 765, 809, 853, 920, 964, 1008, 1052, 1098, 1142, 1186, 1230, 1253, 1297, 1341, 1385, 1431, 1475, 1519, 1563, 1630, 1674, 1718, 1762, 1808, 1852, 1896, 1940, 1963, 2007, 2051

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

A246404, A246405, and A246406 partition the nonnegative integers.

LINKS

Clark Kimberling, Table of n, a(n) for n = 1..2000

MATHEMATICA

z = 500; f[x_] := f[x] = Sec[x];

Select[Range[0, z], f[#] < f[# + 1] &] (* A246404 *)

Select[Range[0, z], f[#] > f[# + 1] < f[# + 2] &] (* A246405 *)

Select[Range[0, z], f[#] > f[# + 1] > f[# + 2] < f[# + 3] &] (* A246406 *)