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Numbers k such that sin(k) < sin(k+1) < sin(k+2) > sin(k+3).
5

%I #10 May 18 2020 12:07:04

%S 0,6,12,18,25,31,37,44,50,56,62,69,75,81,88,94,100,106,113,119,125,

%T 132,138,144,150,157,163,169,175,182,188,194,201,207,213,219,226,232,

%U 238,245,251,257,263,270,276,282,289,295,301,307,314,320,326,333,339

%N Numbers k such that sin(k) < sin(k+1) < sin(k+2) > sin(k+3).

%C The sequences A246293, A246294, A246295, A246296 partition the nonnegative integers.

%C Numbers like 42, 86, 130, 199, 243, 287,.. are in none of these 4 sequences. - _R. J. Mathar_, May 18 2020

%H Clark Kimberling, <a href="/A246295/b246295.txt">Table of n, a(n) for n = 1..1000</a>

%t z = 500; f[x_] := f[x] = Sin[x]; t = Range[0, z];

%t Select[t, f[#] > f[# + 1] &] (* A246293 *)

%t Select[t, f[#] < f[# + 1] > f[# + 2] &] (* A246294 *)

%t Select[t, f[#] < f[# + 1] < f[# + 2] > f[# + 3] &] (* A246295 *)

%t Select[t, f[#] < f[# + 1] < f[# + 2] < f[# + 3] > f[# + 4] &] (* A246296 *)

%Y Cf. A246293, A246294, A246296, A026309 (complement of A246293).

%K nonn,easy

%O 1,2

%A _Clark Kimberling_, Aug 21 2014