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 A256109 #33 Mar 30 2020 08:37:38
%S A256109 33,309,604,13394,17539,1699933,3794579,172330858,2542542111,
%T A256109 8324296445,371247087583,1755524129985,3186699229903,6381820482345
%N A256109 Index of the n-th zero in the first occurrence of a string of exactly n zeros in the decimal expansion of Pi.
%C A256109 a(n) is the least k such that A000796(k-n+1) = ... = A000796(k) = 0 and A000796(k+1) != 0. - _Danny Rorabaugh_, Mar 31 2015
%H A256109 Dave Andersen, <a href="http://www.angio.net/pi/">The Pi-Search Page</a>.
%F A256109 a(n) = A050279(n) + n. - _Danny Rorabaugh_, Mar 31 2015
%o A256109 (PARI) { default(realprecision, 20080); for (m = 1, 10, x = Pi; r = 0; for (n = 1, 20000, d = floor(x); x = (x-d)*10; if(d <> 0, if (r <> m, r = 0, print1(n-1, ", "); r = 0; break), r = r + 1)))}
%Y A256109 Cf. A000796, A050279, A014976, A256160.
%K A256109 nonn,base,more
%O A256109 1,1
%A A256109 _Kival Ngaokrajang_, Mar 14 2015
%E A256109 a(6)-a(10) by _Danny Rorabaugh_, Mar 31 2015
%E A256109 a(11)-a(14) added using A050279 by _Jinyuan Wang_, Mar 30 2020