0, 1, 15, 115, 675, 3451, 16275, 72955, 316275, 1340251, 5590035, 23054395, 94314675, 383578651, 1553331795, 6270493435, 25253701875, 101530450651, 407669649555, 1635323974075, 6555235693875, 26262769508251, 105176572911315, 421082805640315, 1685460823266675, 6745232212623451