Number of 3Xn arrays containing n copies of 0..3-1 with no element 1 greater than its west, northeast or southeast neighbor modulo 3 and the upper left element equal to 0.
A267223
Number of 3Xn arrays containing n copies of 0..3-1 with no element 1 greater than its west, northeast or southeast neighbor modulo 3 and the upper left element equal to 0.
Terms
- a(0) =2a(1) =3a(2) =8a(3) =17a(4) =34a(5) =68a(6) =164a(7) =385a(8) =826a(9) =1848a(10) =4450a(11) =10544a(12) =24056a(13) =56108a(14) =135672a(15) =324720a(16) =762864a(17) =1818110a(18) =4413518a(19) =10641004a(20) =25427616a(21) =61338160a(22) =149415144a(23) =362365684a(24) =875207554a(25) =2127235158a(26) =5197934580a(27) =12666448776a(28) =30813494386a(29) =75278796468
External references
- oeis: A267223