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.

A357359 Maximum number of nodes in an induced path (or chordless path or snake path) in the n X n torus grid graph.

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%I A357359 #9 Oct 01 2022 10:25:29
%S A357359 5,8,14,21,28,39,50
%N A357359 Maximum number of nodes in an induced path (or chordless path or snake path) in the n X n torus grid graph.
%C A357359 It is somewhat unclear how a(n) should be defined for n <= 2. If the 1 X 1 and 2 X 2 torus grid graphs are considered to have loops and multiple edges, respectively, we have a(1) = 0 and a(2) = 1 (unless loops and multiple edges are allowed in a path), otherwise a(1) = 1 and a(2) = 3.
%H A357359 Wikipedia, <a href="https://en.wikipedia.org/wiki/Induced_path">Induced path</a>.
%F A357359 a(n) ~ 2*n^2/3.
%F A357359 a(n) <= (2*n^2-1)/3.
%F A357359 a(n) >= A357358(n) - 1.
%F A357359 a(n) >= A331968(n-1).
%e A357359 Longest induced paths (with one end in the lower left corner) for 3 <= n <= 7:
%e A357359   . X X   . X X .   . X X . X   . X X . X .   . . . X . X X
%e A357359   X X .   X X . .   . X . X X   X X . X X .   X X . X X . X
%e A357359   X . .   X . X .   X X . X .   X . X X . X   . X X . X X .
%e A357359           X . X .   X . X X .   . X X . X X   X . X X . X X
%e A357359                     X . X . .   X X . . X .   X X . X . . .
%e A357359                                 X . X . X .   . X . X . X X
%e A357359                                               X X . X . X .
%Y A357359 Cf. A331968, A357234, A357358.
%K A357359 nonn,more
%O A357359 3,1
%A A357359 _Pontus von Brömssen_, Sep 25 2022