Number of ways to place 5 nonattacking queens on an n X n board.

Terms

a(0) =10a(1) =248a(2) =4618a(3) =46736a(4) =310496a(5) =1535440a(6) =6110256a(7) =20609544a(8) =60963094a(9) =162323448a(10) =396155466a(11) =899046952a(12) =1917743448a(13) =3879011584a(14) =7491080844a(15) =13892164232a(16) =24854703014a(17) =43071383040a(18) =72532831794a(19) =119038462248a(20) =190849299076