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A246294
Numbers k such that sin(k) < sin(k+1) > sin(k+2).
5
1, 7, 13, 19, 26, 32, 38, 45, 51, 57, 63, 70, 76, 82, 89, 95, 101, 107, 114, 120, 126, 133, 139, 145, 151, 158, 164, 170, 176, 183, 189, 195, 202, 208, 214, 220, 227, 233, 239, 246, 252, 258, 264, 271, 277, 283, 290, 296, 302, 308, 315, 321, 327, 334, 340
OFFSET
1,2
COMMENTS
The sequences A246293, A246294, A246295, A246296 partition the nonnegative integers.
Numbers like 42, 86, 130, 199, 243, 287,.. are in none of these 4 sequences. - R. J. Mathar, May 18 2020
LINKS
MATHEMATICA
z = 500; f[x_] := f[x] = Sin[x]; t = Range[0, z];
Select[t, f[#] > f[# + 1] &] (* A246293 *)
Select[t, f[#] < f[# + 1] > f[# + 2] &] (* A246294 *)
Select[t, f[#] < f[# + 1] < f[# + 2] > f[# + 3] &] (* A246295 *)
Select[t, f[#] < f[# + 1] < f[# + 2] < f[# + 3] > f[# + 4] &] (* A246296 *)
Position[Partition[Sin[Range[350]], 3, 1], _?(#[[1]]<#[[2]]>#[[3]]&), 1, Heads-> False]//Flatten (* Harvey P. Dale, Aug 03 2017 *)
CROSSREFS
Cf. A246293, A246295, A246296, A026309 (complement of A246293).
Sequence in context: A123843 A277093 A004082 * A039281 A045115 A331830
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Aug 21 2014
STATUS
approved