# A000490 (b-file synthesized from sequence entry)
0 1
1 16
2 1280
3 249856
4 90767360
5 52975108096
6 45344872202240
7 53515555843342336
8 83285910482761809920
9 165262072909347030040576
10 407227428060372417275494400
11 1219998300294918683087199010816
12 4366953142363907901751614431559680
13 18406538229888710811704852978971181056