Number of (n+2) X (1+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00000101 00010101 or 01010101.

A260008

Number of (n+2) X (1+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00000101 00010101 or 01010101.

Terms

    a(0) =36a(1) =49a(2) =109a(3) =209a(4) =436a(5) =828a(6) =1744a(7) =3344a(8) =7005a(9) =13424a(10) =28067a(11) =53992a(12) =112602a(13) =216997a(14) =451535a(15) =872258a(16) =1811173a(17) =3505729a(18) =7264641a(19) =14089470a(20) =29141208a(21) =56621872a(22) =116900698a(23) =227536583a(24) =468975418a(25) =914316503a(26) =1881490568a(27) =3673849908

External references