# A066723 (b-file synthesized from sequence entry) 0 1 1 1 2 2 3 5 4 13 5 36 6 109 7 340 8 1116 9 3744 10 12981 11 45722 12 165247 13 603242 14 2242932 15 8422438 16 32040585 17 122800802 18 475937009