Number of (n+2) X (3+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00010101 or 01010101.

A259737

Number of (n+2) X (3+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00010101 or 01010101.

Terms

    a(0) =42a(1) =74a(2) =190a(3) =374a(4) =792a(5) =1514a(6) =3480a(7) =6542a(8) =14580a(9) =27866a(10) =62700a(11) =118718a(12) =266548a(13) =506810a(14) =1138004a(15) =2160350a(16) =4852180a(17) =9215834a(18) =20694708a(19) =39301214a(20) =88262564a(21) =167620346a(22) =376424388a(23) =714880094a(24) =1605429620a(25) =3048894554a(26) =6846969460a(27) =13003247390

External references