Number of positive rational knots with 2n+1 crossings.

Terms

a(0) =1a(1) =2a(2) =5a(3) =12a(4) =30a(5) =76a(6) =195a(7) =504a(8) =1309a(9) =3410a(10) =8900a(11) =23256a(12) =60813a(13) =159094a(14) =416325a(15) =1089648a(16) =2852242a(17) =7466468a(18) =19546175a(19) =51170460a(20) =133962621a(21) =350713222a(22) =918170280a(23) =2403786672a(24) =6293172025a(25) =16475700746a(26) =43133883845a(27) =112925875764