Number of possible rook moves on an n X n chessboard.

Terms

a(0) =0a(1) =8a(2) =36a(3) =96a(4) =200a(5) =360a(6) =588a(7) =896a(8) =1296a(9) =1800a(10) =2420a(11) =3168a(12) =4056a(13) =5096a(14) =6300a(15) =7680a(16) =9248a(17) =11016a(18) =12996a(19) =15200a(20) =17640a(21) =20328a(22) =23276a(23) =26496a(24) =30000a(25) =33800a(26) =37908a(27) =42336a(28) =47096a(29) =52200