Number of 1-unbordered words of length n over a 3-letter alphabet beginning with a fixed letter.

A375016

Number of 1-unbordered words of length n over a 3-letter alphabet beginning with a fixed letter.

Terms

    a(0) =1a(1) =1a(2) =3a(3) =7a(4) =21a(5) =57a(6) =171a(7) =499a(8) =1497a(9) =4449a(10) =13347a(11) =39927a(12) =119781a(13) =359001a(14) =1077003a(15) =3230011a(16) =9690033a(17) =29067105a(18) =87201315a(19) =261595047a(20) =784785141a(21) =2354328729a(22) =7062986187a(23) =21188878707a(24) =63566636121a(25) =190699668801a(26) =572099006403

External references