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 A351516 #34 Mar 07 2022 11:32:42 %S A351516 0,0,6,6,8,12,20,24,30,36,48 %N A351516 a(n) is the maximum number of 3-letter words that can be contained in an n X n crossword puzzle. %C A351516 The n X n crossword puzzle grid must contain the maximum number of 3-letter words (and no words of other lengths), and all words must be interconnected (i.e., no word or set of connected words can be completely separated from the other words). %C A351516 The magazine Humor y Juegos Number 13 says that Mariano Pablo Amieva and Solomon Golomb found a general answer to this problem. %D A351516 Jaime Poniachik, Las matemáticas del crucigrama, Revista Humor y Juegos, Número 9, ~ 1981. %H A351516 Rodolfo Kurchan, <a href="https://www.puzzlefun.online/puzzle-fun-35">Problem 781</a>, Puzzle Fun 35, December 2021. %e A351516 4 X 4 solution with a(4) = 6 words by Jaime Poniachik: %e A351516 +---+---+---+---+ %e A351516 | | | |XXX| %e A351516 +---+---+---+---+ %e A351516 |XXX| | | | %e A351516 +---+---+---+---+ %e A351516 |XXX| | | | %e A351516 +---+---+---+---+ %e A351516 |XXX|XXX|XXX| | %e A351516 +---+---+---+---+ %e A351516 . %e A351516 5 X 5 solution with a(5) = 8 words by Jaime Poniachik: %e A351516 +---+---+---+---+---+ %e A351516 | | | |XXX|XXX| %e A351516 +---+---+---+---+---+ %e A351516 | |XXX| | | | %e A351516 +---+---+---+---+---+ %e A351516 | | | |XXX| | %e A351516 +---+---+---+---+---+ %e A351516 |XXX| |XXX|XXX| | %e A351516 +---+---+---+---+---+ %e A351516 |XXX| | | |XXX| %e A351516 +---+---+---+---+---+ %e A351516 . %e A351516 6 X 6 solution with a(6) = 12 words by Jaime Poniachik: %e A351516 +---+---+---+---+---+---+ %e A351516 | | | |XXX|XXX| | %e A351516 +---+---+---+---+---+---+ %e A351516 |XXX| |XXX| | | | %e A351516 +---+---+---+---+---+---+ %e A351516 |XXX| | | |XXX| | %e A351516 +---+---+---+---+---+---+ %e A351516 | |XXX| | | |XXX| %e A351516 +---+---+---+---+---+---+ %e A351516 | | | |XXX| |XXX| %e A351516 +---+---+---+---+---+---+ %e A351516 | |XXX|XXX| | | | %e A351516 +---+---+---+---+---+---+ %e A351516 . %e A351516 Example of an invalid solution: a 6 X 6 solution with a(6) = 12 words, but not valid because some words have 2 letters instead of 3, and the 3-letter words are not all interconnected (black squares completely separate the set of 3-letter words at the upper right from the set of 3-letter words at the lower left): %e A351516 +---+---+---+---+---+---+ %e A351516 | | |XXX| | | | %e A351516 +---+---+---+---+---+---+ %e A351516 | | |XXX| | | | %e A351516 +---+---+---+---+---+---+ %e A351516 |XXX|XXX|XXX| | | | %e A351516 +---+---+---+---+---+---+ %e A351516 | | | |XXX|XXX|XXX| %e A351516 +---+---+---+---+---+---+ %e A351516 | | | |XXX| | | %e A351516 +---+---+---+---+---+---+ %e A351516 | | | |XXX| | | %e A351516 +---+---+---+---+---+---+ %e A351516 . %K A351516 nonn,more %O A351516 1,3 %A A351516 _Rodolfo Kurchan_, Feb 12 2022