Number of ways to place 5 nonattacking nightriders on a 5 X n board.

Terms

a(0) =1a(1) =28a(2) =157a(3) =1248a(4) =4650a(5) =15162a(6) =37988a(7) =86958a(8) =181423a(9) =351708a(10) =648441a(11) =1127392a(12) =1874194a(13) =2988466a(14) =4602096a(15) =6870240a(16) =9983347a(17) =14163972a(18) =19672403a(19) =26812260a(20) =35929480a(21) =47418482a(22) =61723238a(23) =79341720a(24) =100828175a(25) =126796852a(26) =157924785