# A152645 (b-file synthesized from sequence entry) 1 1 2 2 3 6 4 24 5 120 6 720 7 5040 8 40320 9 344640 10 3214080 11 32654592 12 362526336 13 4287655360 14 54096841216 15 740614408736 16 10969734238220