Number of (n+2) X (4+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00010101 or 01010101.

A259738

Number of (n+2) X (4+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00010101 or 01010101.

Terms

    a(0) =62a(1) =136a(2) =374a(3) =868a(4) =1882a(5) =4456a(6) =10570a(7) =24150a(8) =55686a(9) =130032a(10) =301564a(11) =697220a(12) =1617512a(13) =3753468a(14) =8697990a(15) =20161962a(16) =46756582a(17) =108404418a(18) =251306798a(19) =582661346a(20) =1350925528a(21) =3132018192a(22) =7261427776a(23) =16835543314a(24) =39032675868a(25) =90495655752

External references