OFFSET
1,2
COMMENTS
Sequence A141227 gives the maximum number of points visible from some point. By symmetry, when a(n) is odd, the central point in the lattice can see the maximal number of points. When a(n)=1, the central point is the only such point. Apparently the numbers n in A141226 produce both the n x n and n x n x n lattices having central points with maximum visibility.
MATHEMATICA
Table[mx=0; pts=0; Do[cnt=0; Do[If[GCD[d-a, e-b, f-c]<2, cnt++ ], {a, n}, {b, n}, {c, n}]; If[cnt>mx, mx=cnt; pts=1, If[cnt==mx, pts++ ]], {d, n}, {e, n}, {f, n}]; pts, {n, 10}]
CROSSREFS
KEYWORD
nonn
AUTHOR
T. D. Noe, Jun 15 2008
STATUS
approved