A368800 Lower independence number of the n X n torus grid graph C_n square C_n.

3, 4, 5, 8, 13, 16, 18, 20, 27, 32, 39, 42, 45, 56, 65, 72, 76, 80, 95

Offset

3,1

Links

Table of n, a(n) for n=3..21.

Eric Weisstein's World of Mathematics, Lower Independence Number.

Eric Weisstein's World of Mathematics, Torus Grid Graph.

Mathematica

(* conjectured to hold for larger n *)
Table[Piecewise[{
  {n^2/5, Mod[n, 5] == 0},
  {(n + 4) (n - 2)/5, Mod[n, 5] == 1},
  {(n + 8) (2 n^2 + 17 n + 108)/375, Mod[n, 5] == 2},
  {n (n + 2)/5, Mod[n, 5] == 3},
  {n (n + 1)/5, Mod[n, 5] == 4}
}], {n, 3, 21}]

Crossrefs

Sequence in context: A320690 A179070 A358356 * A039020 A055742 A263041

Adjacent sequences: A368797 A368798 A368799 * A368801 A368802 A368803

Keyword

nonn,more,hard

Author

Eric W. Weisstein, Jan 06 2024

Status

approved