a(n) is the permanent of a square matrix M(n) whose general element M_{i,j} is defined by floor((j - i + 1)/2).

A350549

a(n) is the permanent of a square matrix M(n) whose general element M_{i,j} is defined by floor((j - i + 1)/2).

Terms

    a(0) =1a(1) =0a(2) =0a(3) =-1a(4) =2a(5) =20a(6) =-120a(7) =-4608a(8) =41952a(9) =2325024a(10) =-34876800a(11) =-3133087200a(12) =66120252480

External references