# A356530 (b-file synthesized from sequence entry) 0 1 1 1 2 4 3 18 4 156 5 1020 6 23040 7 189000 8 8462160 9 174741840 10 8418513600 11 110288455200 12 26670240273600 13 364684824504000 14 46300470369753600 15 5169242034644688000 16 359472799348030368000 17 7508907247291081632000 18 6157317530690533823616000