# A049131 (b-file synthesized from sequence entry) 1 1 2 1 3 2 4 4 5 10 6 24 7 65 8 171 9 482 10 1338 11 3868 12 11110 13 32707 14 96137 15 287001 16 857577 17 2588794 18 7830730 19 23854028 20 72840384 21 223557060 22 687811608 23 2124300494 24 6576110024 25 20418808851 26 63534855143 27 198178318008 28 619338524116