This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A246306 #8 Apr 01 2024 10:29:35 %S A246306 0,6,13,19,25,32,38,44,50,57,63,69,76,82,88,94,101,107,113,120,126, %T A246306 132,138,145,151,157,164,170,176,182,189,195,201,207,214,220,226,233, %U A246306 239,245,251,258,264,270,277,283,289,295,302,308,314,321,327,333,339 %N A246306 Numbers k such that cos(k) > cos(k+1) > cos(k+2) > cos(k+3) < cos(k+4). %C A246306 The sequences A246303, A246304, A246305, A246306 partition the nonnegative integers. %H A246306 Clark Kimberling, <a href="/A246306/b246306.txt">Table of n, a(n) for n = 1..1000</a> %t A246306 z = 500; f[x_] := f[x] = Cos[x]; t = Range[0, z]; %t A246306 Select[t, f[#] < f[# + 1] &] (* A246303 *) %t A246306 Select[t, f[#] > f[# + 1] < f[# + 2] &] (* A246304 *) %t A246306 Select[t, f[#] > f[# + 1] > f[# + 2] < f[# + 3] &] (* A246305 *) %t A246306 Select[t, f[#] > f[# + 1] > f[# + 2] > f[# + 3] < f[# + 4] &] (* A246306 *) %Y A246306 Cf. A026303, A246304, A246305, A026311 (complement of A246303). %K A246306 nonn,easy %O A246306 1,2 %A A246306 _Clark Kimberling_, Aug 22 2014 %E A246306 Definition corrected by _Georg Fischer_, Apr 01 2024