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 A195678 #11 Aug 13 2020 14:02:28 %S A195678 64,115,1217,1477206,96672,136644591,3640452,6347782194286,72339267, %T A195678 4159327027119583,5595833084,58866692131428799,216432682702 %N A195678 Smallest possible largest element of a 4 by n average array where repetitions are allowed with diagonals. %C A195678 Here, an average array is an array of positive integers such that each number is the average of the numbers in its horizontally, vertically and diagonally adjacent cells. %H A195678 Erich Friedman, <a href="https://erich-friedman.github.io/mathmagic/0399.html">Problem of the month March 1999</a> %K A195678 nonn %O A195678 3,1 %A A195678 _Kausthub Gudipati_, Sep 24 2011