A246293 Numbers k such that sin(k) > sin(k+1).

2, 3, 4, 8, 9, 10, 14, 15, 16, 20, 21, 22, 23, 27, 28, 29, 33, 34, 35, 39, 40, 41, 46, 47, 48, 52, 53, 54, 58, 59, 60, 64, 65, 66, 67, 71, 72, 73, 77, 78, 79, 83, 84, 85, 90, 91, 92, 96, 97, 98, 102, 103, 104, 108, 109, 110, 111, 115, 116, 117, 121, 122, 123

Offset

1,1

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

Clark Kimberling, Table of n, a(n) for n = 1..4000

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[130]], 2, 1], _?(#[[1]]>#[[2]]&), {1}, Heads-> False]//Flatten (* Harvey P. Dale, Sep 18 2016 *)

Prog

(PARI) is(n)=sin(n)>sin(n+1) \\ Charles R Greathouse IV, Aug 03 2017

Crossrefs

Cf. A246294, A246295, A246296, A026309 (complement of A246293).

Sequence in context: A132115 A230998 A184810 * A047228 A032968 A079279

Adjacent sequences: A246290 A246291 A246292 * A246294 A246295 A246296

Keyword

nonn,easy

Author

Clark Kimberling, Aug 21 2014

Status

approved