# A337041 (b-file synthesized from sequence entry) 0 1 1 0 2 5 3 25 4 200 5 1875 6 20625 7 256250 8 3534375 9 53515625 10 881468750 11 15667578125 12 298478828125 13 6060493750000 14 130542772265625 15 2971013486328125 16 71193375156250000 17 1790666151318359375 18 47145509926611328125 19 1296156682961425781250 20 37129279010879638671875