Number of 3Xn arrays containing n copies of 0..3-1 with no element 1 greater than its west or southwest neighbor modulo 3 and the upper left element equal to 0.
A267073
Number of 3Xn arrays containing n copies of 0..3-1 with no element 1 greater than its west or southwest neighbor modulo 3 and the upper left element equal to 0.
Terms
- a(0) =2a(1) =2a(2) =6a(3) =31a(4) =141a(5) =550a(6) =2046a(7) =8149a(8) =34902a(9) =152001a(10) =652150a(11) =2761689a(12) =11707811a(13) =50123854a(14) =216480177a(15) =938377955a(16) =4069585995a(17) =17658916102a(18) =76776575711a(19) =334729181549
External references
- oeis: A267073