1, 2, 3, 8, 24, 73, 230, 751, 2512, 8549, 29520, 103192, 364441, 1298336, 4660273, 16837743, 61187249, 223489715, 820040293, 3021286338, 11172619317, 41454901924, 154285693649, 575826677260, 2154643706124, 8081453618583, 30377809192246, 114421431917805