A246301 Numbers k such that cos(k) < cos(k+1) < cos(k+2) > cos(k+3).

4, 11, 17, 23, 29, 36, 42, 48, 55, 61, 67, 73, 80, 86, 92, 99, 105, 111, 117, 124, 130, 136, 143, 149, 155, 161, 168, 174, 180, 186, 193, 199, 205, 212, 218, 224, 230, 237, 243, 249, 256, 262, 268, 274, 281, 287, 293, 300, 306, 312, 318, 325, 331, 337, 344

Offset: 1

Author

Clark Kimberling, Aug 22 2014

Keywords

• nonn
• easy

Comments

The sequences A026311, A246300, A246301, A246302 partition the nonnegative integers.

Links

• Clark Kimberling, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A026311, A246300, A246302, A246295.

Programs

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 *)