# A158875 (b-file synthesized from sequence entry) 0 1 1 5 2 15 3 45 4 107 5 265 6 615 7 1485 8 3227 9 7225 10 15735 11 35325 12 75019 13 163145 14 348135 15 761805 16 1589147 17 3374905 18 7077495 19 15138045 20 31390219 21 66122825 22 137816295 23 292344525 24 601532059 25 1253593145 26 2591401335 27 5435447805 28 11157226763