OFFSET
3,1
LINKS
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
KEYWORD
nonn,more,hard
AUTHOR
Eric W. Weisstein, Jan 06 2024
STATUS
approved