# A216733 (b-file synthesized from sequence entry) 1 1 2 4 3 54 4 1280 5 44500 6 2095632 7 127881376 8 9819500544 9 928097190000 10 106056995000000 11 14432021983025504 12 2308065337772034048 13 428863163196474895616 14 91656939861553564825600 15 22332165732277725605760000 16 6154560612828089005182025728 17 1905106896258617768240402396928 18 658221263587332244069472967367680 19 252407458471654722567803941053452800