Number of 2-enumeration of 4n X 4n quarter-turn symmetric alternating-sign matrices.
A059487
Number of 2-enumeration of 4n X 4n quarter-turn symmetric alternating-sign matrices.
Terms
- a(0) =1a(1) =2a(2) =80a(3) =53760a(4) =590413824
External references
- oeis: A059487