A246413 Positive integers k satisfying csc(k) > csc(k+1).

1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 45, 47, 49, 51, 53, 55, 57, 59, 61, 63, 65, 68, 70, 72, 74, 76, 78, 80, 82, 84, 86, 88, 89, 91, 93, 95, 97, 99, 101, 103, 105, 107, 109, 112, 114, 116, 118, 120, 122, 124, 126

Offset

1,2

Comments

a(n), A246414, and A246415 partition the positive integers.

Links

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

Mathematica

z = 200;
f[x_] := f[x] = Csc[x];
Select[Range[1, z], f[#] > f[# + 1] &]  (*A246413*)
Select[Range[1, z], f[#] < f[# + 1] > f[# + 2] &]  (*A246414 *)
Select[Range[1, z], f[#] < f[# + 1] < f[# + 2] > f[# + 3] &]  (*A246415*)
Position[Partition[Csc[Range[130]], 2, 1], _?(#[[1]]>#[[2]]&), 1, Heads-> False]// Flatten (* Harvey P. Dale, Jul 27 2020 *)

Crossrefs

Cf. A246414, A246415, A246410 (complement of a(n)).

Sequence in context: A161957 A082720 A033037 * A246411 A158333 A293167

Adjacent sequences: A246410 A246411 A246412 * A246414 A246415 A246416

Keyword

nonn,easy

Author

Clark Kimberling, Aug 25 2014

Status

approved