# A005593 (b-file synthesized from sequence entry) 1 2 2 5 3 12 4 29 5 71 6 177 7 448 8 1147 9 2960 10 7679 11 19989 12 52145 13 136214 14 356121 15 931540 16 2437513 17 6379403 18 16698113 19 43710756 20 114427391 21 299560472 22 784236315 23 2053119817 24 5375076769 25 14072035466 26 36840908237 27 96450492828 28 252510252437