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 A121381 #27 Apr 30 2024 02:27:34
%S A121381 0,4,7,10,13,16,19,22,26,29,32,35,38,41,44,48,51,54,57,60,63,66,70,73,
%T A121381 76,79,82,85,88,92,95,98,101,104,107,110,114,117,120,123,126,129,132,
%U A121381 136,139,142,145,148,151,154,158,161,164,167,170,173,176,180,183,186
%N A121381 a(n) = ceiling(n*Pi).
%H A121381 Vincenzo Librandi, <a href="/A121381/b121381.txt">Table of n, a(n) for n = 0..1000</a>
%t A121381 Table[Ceiling[n Pi], {n, 0, 80}] (* _Vincenzo Librandi_, Feb 22 2013 *)
%o A121381 (PARI) for(n=0,50, print1(ceil(n*Pi), ", ")) \\ _G. C. Greubel_, Oct 28 2017
%o A121381 (Magma) [Ceiling(n*Pi): n in [0..50]]; // _G. C. Greubel_, Oct 28 2017
%Y A121381 Essentially the same as A004084. Cf. A022844, A121854, A121855.
%K A121381 nonn,easy
%O A121381 0,2
%A A121381 _Mohammad K. Azarian_, Sep 06 2006