Number of branched catafusenes with n condensed hexagons.

Terms

a(0) =0a(1) =0a(2) =0a(3) =1a(4) =2a(5) =12a(6) =53a(7) =250a(8) =1115a(9) =5012a(10) =22032a(11) =96746a(12) =422732a(13) =1848128a(14) =8088090a(15) =35498533a(16) =156328706a(17) =691192578a(18) =3068780449a(19) =13683070474a(20) =61267204610a(21) =275455737555