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 A131660 #13 Feb 16 2025 08:33:06
%S A131660 218,241,264,269,280,287,354,1159,1836,1871,1872,1886,1891,1892,1914,
%T A131660 5023,5026,5039,9165,9170,9171,9180,15166,17909,91192,91194,91277,
%U A131660 91289,91290,91293,92029,92031,92033,92038,93913,93927,93928,97369,97839
%N A131660 Positions at which the sum of the digits of e up to that point equals the sum of the digits of Pi up to that point.
%C A131660 Numbers n such that A046974(n) = A046975(n). - _Robert G. Wilson v_, Sep 16 2007
%H A131660 Robert G. Wilson v, <a href="/A131660/b131660.txt">Table of n, a(n) for n = 1..4105</a>.
%H A131660 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/e.html">e</a>.
%H A131660 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/pi.html">PI</a>.
%e A131660 a(1)=218 because the sum of the first 218 digits of e (including the initial 2) equals 987. That is the same result for the first 218 digits of Pi (including the initial 3).
%t A131660 de = First@ RealDigits[E, 10, 10^5]; dse = 0; dpi = First@ RealDigits[Pi, 10, 10^5]; dspi = 0; lst = {}; Do[ dse = dse + de[[n]]; dspi = dspi + dpi[[n]]; If[dse == dspi, AppendTo[lst, n]; Print@n], {n, 10^5}] (* _Robert G. Wilson v_, Sep 16 2007 *)
%t A131660 Module[{nn=100000,ed,pd},ed=Accumulate[RealDigits[E,10,nn][[1]]];pd= Accumulate[ RealDigits[Pi,10,nn][[1]]];Flatten[Position[Thread[ {ed,pd}], _?(#[[1]]==#[[2]]&),{1},Heads->False]]] (* _Harvey P. Dale_, Feb 18 2015 *)
%Y A131660 Cf. A000796, A001113.
%K A131660 base,nonn
%O A131660 1,1
%A A131660 _Sergio Pimentel_, Sep 13 2007
%E A131660 More terms from _Robert G. Wilson v_, Sep 16 2007
%E A131660 a(6) corrected by _N. J. A. Sloane_, Nov 23 2007