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%I #22 Jan 04 2018 03:58:55
%S 22,66,110,154,177,221,265,309,355,399,443,487,554,598,642,686,732,
%T 776,820,864,887,931,975,1019,1065,1109,1153,1197,1264,1308,1352,1396,
%U 1442,1486,1530,1574,1597,1641,1685,1729,1775,1819,1863,1907,1974,2018,2062
%N Positive integers k satisfying csc(k) < csc(k+1) < csc(k+2) > csc(k+3).
%C A246413, A246414, and this sequence partition the positive integers.
%H Clark Kimberling, <a href="/A246415/b246415.txt">Table of n, a(n) for n = 1..1000</a>
%t z = 200;
%t f[x_] := f[x] = Csc[x];
%t Select[Range[1, z], f[#] > f[# + 1] &] (* A246413 *)
%t Select[Range[1, z], f[#] < f[# + 1] > f[# + 2] &] (* A246414 *)
%t Select[Range[1, z], f[#] < f[# + 1] < f[# + 2] > f[# + 3] &] (* A246415 *)
%o (PARI) is(n) = (1/sin(n)) < (1/sin(n+1)) && (1/sin(n+1)) < (1/sin(n+2)) && (1/sin(n+2)) > (1/sin(n+3)) \\ _Felix Fröhlich_, Jan 02 2018
%Y Cf. A246413, A246414.
%K nonn,easy
%O 1,1
%A _Clark Kimberling_, Aug 25 2014
%E Name corrected by _David Gross_, Jan 02 2018
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