Number of nX4 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 1 1 and 1 1 0 vertically.

A207484

Number of nX4 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 1 1 and 1 1 0 vertically.

Terms

    a(0) =9a(1) =81a(2) =217a(3) =530a(4) =1459a(5) =3947a(6) =11306a(7) =32445a(8) =96201a(9) =286920a(10) =873201a(11) =2673027a(12) =8288284a(13) =25824249a(14) =81128201a(15) =255825008a(16) =811028901a(17) =2578371055a(18) =8225731808a(19) =26296176189a(20) =84258830581a(21) =270382678904a(22) =868986130961

External references