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 A146993 #13 Jan 27 2022 08:01:36 %S A146993 1,1,5,1,12,1,24,2,47,2,53,1,70,1 %N A146993 Number of terms in A145848 with exactly 2n decimal digits. %C A146993 It is shown by I. Bernshtein, see link, that a(2n+1)>=1 and 1<=a(2n)<=2. Thanks to Tanya Khovanova for this link. %H A146993 I. Bernshtein, <a href="http://kvant.mccme.ru/1978/06/resheniya_zadachnika_kvanta_ma.htm">Solution of problem M460</a>. %Y A146993 Cf. A145848, A146991. %K A146993 more,nonn,base %O A146993 1,3 %A A146993 _Zak Seidov_, Nov 04 2008 %E A146993 Definition, comment, and a(11) corrected, and a(12)-a(14) added, by _Jon E. Schoenfield_, Nov 19 2008