Number of (n+2)X(6+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00010101 00101011 or 01010101.

A260925

Number of (n+2)X(6+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00010101 00101011 or 01010101.

Terms

    a(0) =491a(1) =831a(2) =3358a(3) =10617a(4) =27582a(5) =81848a(6) =253264a(7) =736065a(8) =2137558a(9) =6366003a(10) =18836612a(11) =55281733a(12) =162975870a(13) =481592042a(14) =1419353824a(15) =4182760615a(16) =12337678966a(17) =36391723458a(18) =107281631494a(19) =316367367773a(20) =932912838818

External references