Number of 4n X 4n quarter-turn symmetric alternating-sign matrices (QTSASM's).

A059476

Number of 4n X 4n quarter-turn symmetric alternating-sign matrices (QTSASM's).

Terms

    a(0) =1a(1) =2a(2) =40a(3) =6860a(4) =9779616a(5) =114640611228

External references