Number of lines through exactly 6 points of an n X n grid of points.

Terms

a(0) =0a(1) =0a(2) =0a(3) =0a(4) =0a(5) =0a(6) =14a(7) =4a(8) =4a(9) =4a(10) =4a(11) =28a(12) =60a(13) =44a(14) =20a(15) =20a(16) =88a(17) =172a(18) =272a(19) =228a(20) =168a(21) =180a(22) =284a(23) =404a(24) =540a(25) =484a(26) =628a(27) =788a(28) =964a(29) =1276