OFFSET
4,2
LINKS
Eric Weisstein's World of Mathematics, Minimum Vertex Coloring.
Eric Weisstein's World of Mathematics, Wheel Complement Graph.
FORMULA
a(n) = (n-1)*((n-1)/2)! for n odd.
a(4) = 1; a(n) = (1/4)*(n - 1)*n^2*(n/2 - 1)! for n even. - Detlef Meya, Apr 14 2024
MATHEMATICA
a[4]:=1; a[n_]:=If[Mod[n, 2]==0, (1/4)*(n-1)*n^2*(n/2-1)!, (n-1)*((n-1)/2)!]; Flatten[Table[a[n], {n, 4, 31}]] (* Detlef Meya, Apr 14 2024 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Eric W. Weisstein, Mar 15 2024
EXTENSIONS
More terms (20-31) from Detlef Meya, Apr 14 2024
STATUS
approved