a(n) = number of n-lettered words in the alphabet {1, 2, 3} with as many occurrences of the substring (consecutive subword) [1, 1, 2] as of [3, 1, 1].
A211295
a(n) = number of n-lettered words in the alphabet {1, 2, 3} with as many occurrences of the substring (consecutive subword) [1, 1, 2] as of [3, 1, 1].
Terms
- a(0) =1a(1) =3a(2) =9a(3) =25a(4) =71a(5) =203a(6) =585a(7) =1689a(8) =4881a(9) =14113a(10) =40839a(11) =118287a(12) =342951a(13) =995303a(14) =2891309a(15) =8406925a(16) =24466555a(17) =71267575a(18) =207771209a(19) =606238465a(20) =1770339721a(21) =5173862121a(22) =15132414675a(23) =44292151875a(24) =129736008621a(25) =380276585553
External references
- oeis: A211295