# A274268 (b-file synthesized from sequence entry) 1 1 2 7 3 26 4 50 5 24 6 -24 7 48 8 -144 9 576 10 -2880 11 17280 12 -120960 13 967680 14 -8709120 15 87091200 16 -958003200 17 11496038400 18 -149448499200 19 2092278988800 20 -31384184832000 21 502146957312000 22 -8536498274304000 23 153656968937472000 24 -2919482409811968000 25 58389648196239360000