# A341233 (b-file synthesized from sequence entry) 1 1 2 1 3 12 4 96 5 320 6 3840 7 161280 8 516096 9 46448640 10 185794560 11 2270822400 12 163499212800 13 1821848371200 14 51011754393600 15 10712468422656000 16 9794256843571200 17 555007887802368000 18 139861987726196736000 19 1449478781889675264000 20 49059281848573624320000