OFFSET
1,2
LINKS
J.-P. Bode and H. Harborth, Independence for knights on hexagon and triangle boards, Discrete Math., 272 (2003), 27-35.
Andy Huchala, Python program.
FORMULA
a(4*n+1) = 3*n^2 + 3*n + 1 = A003215(n) from Bode and Harborth. - Andy Huchala, Mar 16 2024
CROSSREFS
KEYWORD
nonn,more
AUTHOR
N. J. A. Sloane, Oct 21 2003
EXTENSIONS
a(17)-a(25) from Andy Huchala, Mar 16 2024
STATUS
approved