# A197131 (b-file synthesized from sequence entry) 2 4 3 46 4 544 5 7216 6 108096 7 1816704 8 33951744 9 699512832 10 15765626880 11 386046443520 12 10208951009280 13 290039357767680 14 8811722692362240 15 285113464809062400 16 9789232245217689600 17 355501479519741542400 18 13615286053738276454400 19 548476851979845579571200