Number of nX2 0..1 arrays with every element unequal to 1, 2, 3 or 4 king-move adjacent elements, with upper left element zero.

A303890

Number of nX2 0..1 arrays with every element unequal to 1, 2, 3 or 4 king-move adjacent elements, with upper left element zero.

Terms

    a(0) =1a(1) =7a(2) =23a(3) =86a(4) =313a(5) =1145a(6) =4184a(7) =15293a(8) =55895a(9) =204294a(10) =746685a(11) =2729101a(12) =9974744a(13) =36457249a(14) =133249635a(15) =487021534a(16) =1780042209a(17) =6505975697a(18) =23779053976a(19) =86911392597a(20) =317657303391

External references