# A124461 (b-file synthesized from sequence entry) 0 1 1 2 2 4 3 9 4 23 5 66 6 210 7 731 8 2744 9 10959 10 46058 11 202028 12 919386 13 4321837 14 20916763 15 103958935 16 529512396 17 2759340117 18 14690668955 19 79813438230 20 442057104246 21 2493917931493 22 14320972817368 23 83652035642564 24 496769855224824