# A153997 (b-file synthesized from sequence entry) 0 1 1 2 2 2 3 4 4 16 5 31 6 122 7 973 8 3890 9 30317 10 486144 11 3845485 12 61098761 13 1952652536 14 30753790733 15 973261651722 16 61980407029298 17 1943138871957133 18 122570367648067555