Number of (n+1) X 3 0..2 arrays with the number of clockwise edge increases in every 2 X 2 subblock equal to one, and every 2 X 2 determinant nonzero.

A206004

Number of (n+1) X 3 0..2 arrays with the number of clockwise edge increases in every 2 X 2 subblock equal to one, and every 2 X 2 determinant nonzero.

Terms

    a(0) =78a(1) =300a(2) =980a(3) =3706a(4) =12304a(5) =45810a(6) =154346a(7) =567112a(8) =1932816a(9) =7031026a(10) =24170780a(11) =87268194a(12) =301959592a(13) =1084079204a(14) =3769438358a(15) =13475470000a(16) =47028047126a(17) =167585570856a(18) =586477834058

External references