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 A121900 #22 Sep 08 2022 08:45:27
%S A121900 0,1,1,1,1,1,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,3,3,3,3,3,3,3,3,3,3,3,
%T A121900 3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,
%U A121900 4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,5,5,5,5
%N A121900 a(n) = ceiling((Pi - e)*sqrt(n)).
%H A121900 Vincenzo Librandi, <a href="/A121900/b121900.txt">Table of n, a(n) for n = 0..999</a> [Offset shifted by _Georg Fischer_, Sep 02 2022]
%t A121900 Table[Ceiling[(Pi - E) Sqrt[n]], {n, 0, 110}] (* _Vincenzo Librandi_, Feb 21 2013 *)
%o A121900 (PARI) for(n=0,50, print1(ceil((Pi - exp(1))*sqrt(n)), ", ")) \\ _G. C. Greubel_, Oct 28 2017
%o A121900 (Magma) C<i> := ComplexField(); [Ceiling((Pi(C) - Exp(1))*Sqrt(n)): n in [0..50]]; // _G. C. Greubel_, Oct 28 2017
%Y A121900 Cf. A073244 (Pi-e), A121854, A121855, A121856, A121857.
%K A121900 nonn,easy
%O A121900 0,7
%A A121900 _Mohammad K. Azarian_, Sep 01 2006
%E A121900 Offset corrected by _Mohammad K. Azarian_, Nov 20 2008
%E A121900 Offset changed to 0 by _Georg Fischer_, Sep 02 2022