# A003939 (b-file synthesized from sequence entry) 1 1451520 2 4585351680 3 4106059776000 4 228501000000000 5 273457218604953600 6 9077005607176765440 7 54025731402499584000 8 3669292720793456064000 9 122796979335906113871360 10 19266960106724096212992000