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 A158242 #16 Apr 23 2020 10:04:04 %S A158242 1,10,102,1024,10245,102456,1024569,12965408,381654720,3816547290 %N A158242 Smallest n-digit number with distinct digits such that every k-digit substring (k <= n) taken from the left is divisible by k (k = 1..n). %C A158242 Years ago, the columnist Alex Bellos asked John Conway for some math puzzles for his column. A few days after Conway's death in 2020, Bellos published two of those puzzles. a(10) of this sequence is the solution to the second puzzle. See the Bellos (2020) link. - _Alonso del Arte_, Apr 21 2020 %H A158242 Alex Bellos, <a href="https://www.theguardian.com/science/2020/apr/20/did-you-solve-it-john-horton-conway-playful-maths-genius">Did you solve it? John Horton Conway, playful maths genius</a>, The Guardian, April 20, 2020. %e A158242 12965408, for instance, is in the sequence because 1|1, 2|12, 3|129, 4|1296, 5|12965, 6|129654, 7|1296540, 8|12965408. It's a(8). %Y A158242 Cf. A158240. %K A158242 nonn,base,fini,full %O A158242 1,2 %A A158242 _Lekraj Beedassy_, Mar 14 2009 %E A158242 a(8), a(9) corrected by _Ray Chandler_, Mar 21 2009