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 A353093 #16 Apr 29 2022 15:53:26 %S A353093 3,6,10,13,16,20,23 %N A353093 Solution to Forest of Numbers (Bosque de Números) puzzle for Opaque Queens starting with numbers 1 and 2 for an n X n square grid (see Comments). %C A353093 Start with an n X n square grid. Each cell has neighbors horizontally, vertically and diagonally. Place the numbers 1 and 2 anywhere. Now place the numbers 3, 4, ..., m in order, subject to the rule that when you place k, the sum of the numbers that a Chess Queen attack in the same row, column and diagonal must equal k. Then a(n) is the maximum m that can be achieved. %H A353093 Rodolfo Kurchan, <a href="https://www.puzzlefun.online/problems">Puzzle Fun, Problems, Forest of Numbers</a> %e A353093 Solution for a(5) = 13 from Daniel Valdano: %e A353093 +---+---+---+---+---+ %e A353093 | 12| 4 | 8 | | | %e A353093 +---+---+---+---+---+ %e A353093 | 7 | 1 | 3 | | 10| %e A353093 +---+---+---+---+---+ %e A353093 | | | 6 | | | %e A353093 +---+---+---+---+---+ %e A353093 | | 9 | 2 | 13| 5 | %e A353093 +---+---+---+---+---+ %e A353093 | | 11| | | | %e A353093 +---+---+---+---+---+ %e A353093 Solution for a(6) = 16 from Daniel Valdano. %e A353093 Solution for a(7) = 20 from Giorgio Vecchi. %e A353093 Solution for a(8) = 23 from Giorgio Vecchi. %Y A353093 Cf. A352814, A350627, A353070. %K A353093 nonn,more %O A353093 2,1 %A A353093 _Rodolfo Kurchan_, Apr 22 2022