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A327422
Positive integers k such that tan(k) > 0 (or equivalently, cot(k) > 0).
6
1, 4, 7, 10, 13, 14, 16, 17, 19, 20, 22, 23, 26, 29, 32, 35, 36, 38, 39, 41, 42, 44, 45, 48, 51, 54, 57, 58, 60, 61, 63, 64, 66, 67, 70, 73, 76, 79, 80, 82, 83, 85, 86, 88, 89, 92, 95, 98, 101, 102, 104, 105, 107, 108, 110, 111, 114, 117, 120, 123, 124, 126, 127, 129
OFFSET
1,2
COMMENTS
Complement of A327423.
Numbers k such that 0 < {k/Pi} < 1/2, where {} is the fractional part.
Numbers k such that A330035(k) = +1.
Also positive integers k such that sin(2k) > 0, i.e., k such that 2k is in A070752.
LINKS
MATHEMATICA
upto[n_] := Select[Range[n], Tan[#] > 0 &]
A327422={}; Do[ If[Tan[n] > 0, AppendTo[A327422, n]], {n, 200}]; A327422 (* K. D. Bajpai, Dec 15 2019 *)
Select[Range[130], Tan[#]>0&] (* Harvey P. Dale, Aug 26 2021 *)
PROG
(PARI) A327422_up_to_n(n) = my(v=vector(n, k, k)); select(k->tan(k)>0, v)
(Magma) [n : n in[1..300]|Tan(n) gt 0]; // K. D. Bajpai, Dec 15 2019
CROSSREFS
Cf. A070752 (sin(k) > 0 or csc(k) > 0), A070751 (sin(k) < 0 or csc(k) < 0), A131503 (cos(k) > 0 or sec(k) > 0), this sequence (tan(k) > 0 or cot(k) > 0), A327423 (tan(k) < 0 or cot(k) < 0).
Sequence in context: A184850 A331207 A090384 * A260165 A055054 A196415
KEYWORD
nonn
AUTHOR
Jianing Song, Nov 29 2019
STATUS
approved