Number of strings of length n defined on {0, 1, 2, 3} that contain one or no 1's, two or no 2's, three or no 3's and any number of 0's.
A385407
Number of strings of length n defined on {0, 1, 2, 3} that contain one or no 1's, two or no 2's, three or no 3's and any number of 0's.
Terms
- a(0) =1a(1) =2a(2) =4a(3) =11a(4) =31a(5) =86a(6) =282a(7) =939a(8) =2781a(9) =7186a(10) =16496a(11) =34387a(12) =66299a(13) =119926a(14) =205766a(15) =337731a(16) =533817a(17) =816834a(18) =1215196a(19) =1763771a(20) =2504791a(21) =3488822a(22) =4775794a(23) =6436091a(24) =8551701a(25) =11217426a(26) =14542152a(27) =18650179a(28) =23682611a(29) =29798806
External references
- oeis: A385407