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, 2, 1].
A211294
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, 2, 1].
Terms
- a(0) =1a(1) =3a(2) =9a(3) =25a(4) =69a(5) =193a(6) =543a(7) =1533a(8) =4341a(9) =12331a(10) =35131a(11) =100369a(12) =287511a(13) =825643a(14) =2376563a(15) =6855891a(16) =19818729a(17) =57402023a(18) =166556929a(19) =484093953a(20) =1409218111a(21) =4108293369a(22) =11993207211a(23) =35055708423a(24) =102587243163a(25) =300540887595a(26) =881366127909
External references
- oeis: A211294