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 A054544 #17 Feb 06 2022 18:17:29 %S A054544 1,1,2,3,9,70,117,503,648,1078,12868,41235,178650,377670,394301, %T A054544 546185,2600672,8729780,41318679,83367169,525961060,561571346, %U A054544 1556964264,1868773845,15139200289,27297789005,30324107039,56699922000 %N A054544 Engel series expansion (or "Egyptian product") for Khintchine's constant. %D A054544 Steven R. Finch, Mathematical Constants, Cambridge, 2003, pp. 59-65. %H A054544 Steven R. Finch, <a href="http://www.people.fas.harvard.edu/~sfinch/constant/khntchn/khntchn.html">Khintchine's Constant</a> [Broken link] %H A054544 Steven R. Finch, <a href="http://web.archive.org/web/20011108021950/http://www.mathsoft.com/asolve/constant/khntchn/khntchn.html">Khintchine's Constant</a> [From the Wayback machine] %H A054544 <a href="/index/El#Engel">Index entries for sequences related to Engel expansions</a> %Y A054544 Cf. A002210, A006784, A028254, A028257. %K A054544 nonn %O A054544 0,3 %A A054544 _Jeppe Stig Nielsen_, Apr 09 2000