Number of signed permutations of length 2n invariant under D and D'bar.
A193778
Number of signed permutations of length 2n invariant under D and D'bar.
Terms
- a(0) =1a(1) =2a(2) =8a(3) =32a(4) =160a(5) =832a(6) =4864a(7) =29696a(8) =195584a(9) =1341440a(10) =9723904a(11) =73105408a(12) =574062592a(13) =4657184768a(14) =39165624320a(15) =339133595648
External references
- oeis: A193778