Number of nX3 0..1 arrays with every element unequal to 0, 1, 2 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

A318070

Number of nX3 0..1 arrays with every element unequal to 0, 1, 2 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

Terms

    a(0) =4a(1) =10a(2) =18a(3) =41a(4) =81a(5) =179a(6) =404a(7) =893a(8) =2000a(9) =4516a(10) =10125a(11) =22737a(12) =51181a(13) =115034a(14) =258515a(15) =581380a(16) =1307094a(17) =2938317a(18) =6606445a(19) =14853275a(20) =33392840a(21) =75076165a(22) =168791772a(23) =379483956a(24) =853176349a(25) =1918162541a(26) =4312510121a(27) =9695613622a(28) =21798217755

External references