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 A004084 #16 Mar 21 2013 06:36:42
%S A004084 1,4,7,10,13,16,19,22,26,29,32,35,38,41,44,48,51,54,57,60,63,66,70,73,
%T A004084 76,79,82,85,88,92,95,98,101,104,107,110,114,117,120,123,126,129,132,
%U A004084 136,139,142,145,148,151,154,158,161,164,167
%N A004084 a(n) = n-th positive integer k such that tan(k-1) <= 0 and tan(k) > 0.
%C A004084 Gives integer solutions >1 to the equation x=ceiling(r*floor(x/r)) where r=Pi. - _Benoit Cloitre_, Feb 14 2004
%F A004084 a(n) = ceiling(Pi*(n-1)) for n>1. - _Benoit Cloitre_, Feb 14 2004
%o A004084 (PARI) lista(m) = {for (i=1, m, if ((tan(i-1)<=0) && (tan(i) > 0), print1(i, ", ")););} \\ _Michel Marcus_, Mar 21 2013
%K A004084 nonn
%O A004084 1,2
%A A004084 _Clark Kimberling_