T(n,k)=Number of (n+1)X(n+1) 0..k arrays with each 2X2 subblock determinant nonzero and the array of 2X2 subblock determinants symmetric under horizontal and vertical reflection.

A187699

T(n,k)=Number of (n+1)X(n+1) 0..k arrays with each 2X2 subblock determinant nonzero and the array of 2X2 subblock determinants symmetric under horizontal and vertical reflection.

Terms

    a(0) =6a(1) =50a(2) =0a(3) =192a(4) =8a(5) =104a(6) =512a(7) =74a(8) =7954a(9) =0a(10) =1126a(11) =280a(12) =87258a(13) =1548a(14) =9350a(15) =2146a(16) =784a(17) =692410a(18) =22738a(19) =15128848a(20) =0a(21) =3760a(22) =1970a(23) =2363474a(24) =320674a(25) =1089964504a(26) =454640a(27) =4280018a(28) =6112a(29) =3580

External references