Number of (n+2) X (1+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00000001 00000011 or 00010001.

A260537

Number of (n+2) X (1+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00000001 00000011 or 00010001.

Terms

    a(0) =40a(1) =75a(2) =193a(3) =337a(4) =582a(5) =1350a(6) =2732a(7) =5037a(8) =10549a(9) =21615a(10) =41842a(11) =84846a(12) =172576a(13) =341567a(14) =686447a(15) =1387291a(16) =2770696a(17) =5557618a(18) =11190652a(19) =22426331a(20) =44981821a(21) =90410789a(22) =181399432a(23) =363944476a(24) =730917000a(25) =1467035943a(26) =2944001797a(27) =5910524039

External references