Number of alternating sign n X n matrices symmetric with respect to both diagonals.
A005162
Number of alternating sign n X n matrices symmetric with respect to both diagonals.
Terms
- a(0) =1a(1) =2a(2) =3a(3) =8a(4) =15a(5) =52a(6) =126a(7) =568a(8) =1782a(9) =10436a(10) =42471a(11) =323144a(12) =1706562a(13) =16866856a(14) =115640460a(15) =1484714416a(16) =13216815036a(17) =220426128584
External references
- oeis: A005162