346128domain: NAppears in sequencesExpansion of 1/(1 - x - x^2 + x^4 - x^6).at n=32A117791Number of closed knight's tour diagrams of a 3 X n chessboard that have "Bergholtian symmetry".at n=28A169766E.g.f.: tan(x)/(1+LambertW(-x)).at n=7A277467