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, 3].
A211293
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, 3].
Terms
- a(0) =1a(1) =3a(2) =9a(3) =25a(4) =69a(5) =191a(6) =531a(7) =1485a(8) =4173a(9) =11779a(10) =33381a(11) =94947a(12) =270979a(13) =775809a(14) =2227607a(15) =6413441a(16) =18510645a(17) =53548119a(18) =155231177a(19) =450869943a(20) =1311874981a(21) =3823307463a(22) =11159216577a(23) =32615423715a(24) =95446283091a(25) =279639107073a(26) =820162536291
External references
- oeis: A211293