T(n,k)=Number of (n+1)X(k+1) 0..3 arrays with every 2X2 subblock summing to a nonzero multiple of 3.

A251343

T(n,k)=Number of (n+1)X(k+1) 0..3 arrays with every 2X2 subblock summing to a nonzero multiple of 3.

Terms

    a(0) =85a(1) =455a(2) =455a(3) =2450a(4) =3315a(5) =2450a(6) =13275a(7) =24714a(8) =24714a(9) =13275a(10) =72375a(11) =189129a(12) =263824a(13) =189129a(14) =72375a(15) =397000a(16) =1487375a(17) =3014066a(18) =3014066a(19) =1487375a(20) =397000a(21) =2190625a(22) =12022920a(23) =36988354a(24) =55048995a(25) =36988354a(26) =12022920a(27) =2190625a(28) =12156875a(29) =99776859

External references