# A251580 (b-file synthesized from sequence entry) 0 1 1 1 2 10 3 280 4 13960 5 1023760 6 99935200 7 12226859200 8 1801725932800 9 310890328768000 10 61516405597830400 11 13735605457885312000 12 3416919943285809280000 13 937247149729410729472000 14 281051240591439955878400000 15 91474949907165746668607488000 16 32117399444469103248129863680000