Minimal number of knights needed to cover an n X n board.

Terms

a(0) =1a(1) =4a(2) =4a(3) =4a(4) =5a(5) =8a(6) =10a(7) =12a(8) =14a(9) =16a(10) =21a(11) =24a(12) =28a(13) =32a(14) =36a(15) =40a(16) =46a(17) =52a(18) =57a(19) =62a(20) =68