a(n) is the number of reflectable bases of the root system of type D_n.

A321233

a(n) is the number of reflectable bases of the root system of type D_n.

Terms

    a(0) =0a(1) =4a(2) =128a(3) =4992a(4) =241664a(5) =14131200a(6) =972521472a(7) =77138231296

External references