# A003771 (b-file synthesized from sequence entry) 1 3 2 30 3 198 4 1326 5 8886 6 59550 7 399078 8 2674446 9 17922966 10 120111870 11 804937158 12 5394336366 13 36150480246 14 242264688990 15 1623551862438 16 10880333659086 17 72915231888726 18 488645955902910 19 3274691227542918 20 21945546680994606 21 147069444311876406 22 985595016821145630