Number of ways to place 4 points on an n X n square grid so that no more than 2 points are on a vertical or horizontal straight line.

A279438

Number of ways to place 4 points on an n X n square grid so that no more than 2 points are on a vertical or horizontal straight line.

Terms

    a(0) =0a(1) =1a(2) =90a(3) =1428a(4) =10600a(5) =51525a(6) =190806a(7) =584080a(8) =1552608a(9) =3701025a(10) =8088850a(11) =16470036a(12) =31616520a(13) =57743413a(14) =101055150a(15) =170433600a(16) =278290816a(17) =441610785a(18) =683206218a(19) =1033218100a(20) =1530887400a(21) =2226630021a(22) =3184447750a(23) =4484709648a(24) =6227340000a(25) =8535450625a(26) =11559457026a(27) =15481719540

External references