cp's OEIS Frontend

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.

A357500 Largest number of nodes of an induced path in the n X n knight graph.

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%I A357500 #23 Jan 31 2023 01:13:15
%S A357500 1,1,7,9,15,21,24,34
%N A357500 Largest number of nodes of an induced path in the n X n knight graph.
%D A357500 Thomas Dawson, Échecs Féeriques, L'Échiquier, volume 2, issue 2, 1930; issue 3, 1931.
%D A357500 Donald E. Knuth, The Art of Computer Programming, Volume 4B, Combinatorial Algorithms, Part 2, Addison-Wesley, 2023. See exercise 7.2.2.1-172 and its solution.
%H A357500 Nikolai Beluhov, <a href="https://arxiv.org/abs/2301.01152">Snake paths in king and knight graphs</a>, arXiv:2301.01152 [math.CO], 2023.
%H A357500 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/KnightGraph.html">Knight Graph</a>.
%H A357500 Wikipedia, <a href="https://en.wikipedia.org/wiki/Induced_path">Induced path</a>
%F A357500 a(n) >= A165143(n) - 1 for n >= 3.
%F A357500 a(n) <= (4*(n^2+3*n-2)-1)/7 for n >= 4. - _Elijah Beregovsky_, Dec 22 2022
%F A357500 a(n) = n^2/2 + O(n) (Beluhov 2023). - _Pontus von Brömssen_, Jan 30 2023
%e A357500 Longest paths for 3 <= n <= 7:
%e A357500   X . X   . . . .   . X . X .   . X X X . .   X . X X X . .
%e A357500   X . X   X . X X   X X . X X   X . . X X X   X . X . . X .
%e A357500   X X X   . X X .   X . . . X   X . . . X X   . X X . . X .
%e A357500           X X X X   X X . X X   X X . . . X   . . X . . X X
%e A357500                     . X X X .   . X X . X X   . . . . . . X
%e A357500                                 . X X X X .   . X X X X X X
%e A357500                                               X X . X X . .
%Y A357500 Cf. A165143, A331968.
%K A357500 nonn,more
%O A357500 1,3
%A A357500 _Pontus von Brömssen_, Oct 01 2022