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 [2, 1, 1].
A211292
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 [2, 1, 1].
Terms
- a(0) =1a(1) =3a(2) =9a(3) =25a(4) =71a(5) =205a(6) =591a(7) =1707a(8) =4941a(9) =14319a(10) =41541a(11) =120643a(12) =350713a(13) =1020483a(14) =2972017a(15) =8663153a(16) =25273679a(17) =73793509a(18) =215632759a(19) =630591329a(20) =1845473587a(21) =5404857441a(22) =15840441819a(23) =46456569717a(24) =136337104383a(25) =400367192229
External references
- oeis: A211292