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 A138114 #8 Jun 05 2025 11:11:03
%S A138114 3,3,1,3,1,4,3,1,4,1,3,1,4,1,5,3,1,4,1,5,9,3,1,4,1,5,9,2,3,1,4,1,5,9,
%T A138114 2,6,3,1,4,1,5,9,2,6,5,3,1,4,1,5,9,2,6,5,3,3,1,4,1,5,9,2,6,5,3,5,3,1,
%U A138114 4,1,5,9,2,6,5,3,5,8
%N A138114 Triangle read by rows: row n lists the first n digits of the decimal expansion of Pi.
%e A138114 Triangle begins:
%e A138114 ..... 3
%e A138114 .... 3,1
%e A138114 ... 3,1,4
%e A138114 .. 3,1,4,1
%e A138114 . 3,1,4,1,5
%t A138114 s={};Do[AppendTo[s,RealDigits[Pi,10,n][[1]]],{n,12}];s//Flatten (* _James C. McMahon_, Jun 05 2025 *)
%Y A138114 Cf. A000796, A138070, A138071.
%K A138114 easy,nonn,tabl,base
%O A138114 1,1
%A A138114 _Omar E. Pol_, Mar 14 2008