# A153921 (b-file synthesized from sequence entry) 0 1 1 2 2 4 3 10 4 28 5 148 6 714 7 6039 8 49623 9 697824 10 9570390 11 228608398 12 5268376882 13 211052632687 14 8181458661819 15 550685739585810 16 35868897568521948 17 4059582510922093828 18 444431993377350866570 19 84536428851931450778591