# A121302 (b-file synthesized from sequence entry) 1 1 2 1 3 4 4 10 5 28 6 75 7 202 8 540 9 1440 10 3828 11 10153 12 26875 13 71021 14 187421 15 494013 16 1300844 17 3422509 18 8998118 19 23642479 20 62088032 21 162978242 22 427648023 23 1121766397 24 2941697012 25 7712415568 26 20215976824 27 52981414253 28 138831400836