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A246302
Numbers k such that cos(k) < cos(k+1) < cos(k+2) < cos(k+3) > cos(k+4).
4
3, 10, 16, 22, 28, 35, 41, 47, 54, 60, 66, 72, 79, 85, 91, 98, 104, 110, 116, 123, 129, 135, 142, 148, 154, 160, 167, 173, 179, 185, 192, 198, 204, 211, 217, 223, 229, 236, 242, 248, 255, 261, 267, 273, 280, 286, 292, 299, 305, 311, 317, 324, 330, 336, 343
OFFSET
1,1
COMMENTS
The sequences A026311, A246300, A246301, A246302 partition the nonnegative integers.
LINKS
MATHEMATICA
z = 520; f[x_] := f[x] = Cos[x]; t = Range[0, z];
Select[t, f[#] > f[# + 1] &] (* A026311 *)
Select[t, f[#] < f[# + 1] > f[# + 2] &] (* A246300 *)
Select[t, f[#] < f[# + 1] < f[# + 2] > f[# + 3] &] (* A246301 *)
Select[t, f[#] < f[# + 1] < f[# + 2] < f[# + 3] > f[# + 4] &] (* A246302 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Aug 22 2014
STATUS
approved