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 A036904 #36 Feb 16 2025 08:32:37
%S A036904 21,372,8092,102128,1061613,12108841,198150341,1929504534
%N A036904 Scan decimal expansion of e until all n-digit strings have been seen; a(n) is number of digits that must be scanned.
%C A036904 The digits scanned are {2, 7, 1, 8, 2, 8, ...}, so the initial 2 in 2.71828... is included and counted as the first digit.
%H A036904 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/ConstantDigitScanning.html">Constant Digit Scanning</a>
%H A036904 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/eDigits.html">e Digits</a>
%Y A036904 Cf. A001113 (decimal expansion of e).
%Y A036904 Cf. A036900 (last number encountered when scanning the decimal expansion of e for all n-digit strings).
%Y A036904 Cf. A088576 (starting positions of the first occurrence of n in the decimal expansion of e).
%Y A036904 Cf. A032510, A036900-A036906.
%K A036904 nonn,base,more
%O A036904 1,1
%A A036904 _Michael Kleber_
%E A036904 a(7) from _Piotr Idzik_, Nov 01 2011
%E A036904 a(8) from _Eric W. Weisstein_, Sep 11 2013