The first major verification of this work was done in the 1960s by John Horton Conway, who not only developed a new notation but also the Alexander–Conway polynomial . This verified the list of knots of at most 11 crossings and a new list of links up to 10 crossings. Conway found a number of omissions but only one duplication in the Tait–Little tables; however he missed the duplicates called the Perko pair, which would only be noticed in 1974 by Kenneth Perko . This famous error would propagate when Dale Rolfsen added a knot table in his influential text, based on Conway's work. Conway's 1970 paper on knot theory also contains a typographical duplication on its non-alternating 11-crossing knots page and omits 4 examples — 2 previously listed in D. Lombardero's 1968 Princeton senior thesis and 2 more subsequently discovered by Alain Caudron. [see Perko (1982), Primality of certain knots, Topology Proceedings] Less famous is the duplicate in his 10 crossing link table: 2.-2.-20.20 is the mirror of 8*-20:-20. [See Perko (2016), Historical highlights of non-cyclic knot theory, J. Knot Theory Ramifications].
the first major verification of this work was done in the 1960s by john horton conway who not only developed a new notation but also the alexander–conway polynomial  this verified the list of knots of at most 11 crossings and a new list of links up to 10 crossings conway found a number of omissions but only one duplication in the tait–little tables; however he missed the duplicates called the perko pair which would only be noticed in 1974 by kenneth perko  this famous error would propagate when dale rolfsen added a knot table in his influential text based on conway's work conway's 1970 paper on knot theory also contains a typographical duplication on its non-alternating 11-crossing knots page and omits 4 examples — 2 previously listed in d lombardero's 1968 princeton senior thesis and 2 more subsequently discovered by alain caudron [see perko (1982) primality of certain knots topology proceedings] less famous is the duplicate in his 10 crossing link table 2-2-2020 is the mirror of 8*-20-20 [see perko (2016) historical highlights of non-cyclic knot theory j knot theory ramifications]