[0,2,2,6,14,39,125,399,1310,4356,14970,51715, 178832,635778,2290019,8106059,29234378,105635076, 384409483,1408730050,5193316109,19170300330, 71421970661,263893092145,984568438169, 3686368605467,13838552783467,52008816746450]