Number of n X 3 0..1 arrays with rows and columns lexicographically nondecreasing and every element equal to at least one horizontal or vertical neighbor.

A201348

Number of n X 3 0..1 arrays with rows and columns lexicographically nondecreasing and every element equal to at least one horizontal or vertical neighbor.

Terms

    a(0) =2a(1) =8a(2) =18a(3) =47a(4) =118a(5) =273a(6) =585a(7) =1174a(8) =2228a(9) =4030a(10) =6992a(11) =11697a(12) =18950a(13) =29839a(14) =45807a(15) =68736a(16) =101044a(17) =145796a(18) =206830a(19) =288899a(20) =397830a(21) =540701a(22) =726037a(23) =964026a(24) =1266756a(25) =1648474a(26) =2125868a(27) =2718373a(28) =3448502a(29) =4342203

External references