Number of nX3 0..1 arrays with every element unequal to 2, 3, 4 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

A318217

Number of nX3 0..1 arrays with every element unequal to 2, 3, 4 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

Terms

    a(0) =0a(1) =1a(2) =4a(3) =18a(4) =86a(5) =413a(6) =1975a(7) =9474a(8) =45415a(9) =217714a(10) =1043722a(11) =5003565a(12) =23986950a(13) =114992767a(14) =551272103a(15) =2642783040a(16) =12669427963a(17) =60736883262a(18) =291170919400

External references