# A151270 (b-file synthesized from sequence entry) 0 1 1 1 2 4 3 9 4 30 5 90 6 286 7 941 8 3072 9 10308 10 34814 11 118138 12 406368 13 1399630 14 4858636 15 16948153 16 59302432 17 208587930 18 735602234 19 2602943312 20 9239044912 21 32867768218 22 117244508016 23 419105764722 24 1501220073148 25 5388115272948 26 19371438711296 27 69764776854918 28 251641664047600 29 908984140277160 30 3288068461179108