Number of positive words of length n in the monoid Br_6 of positive braids on 7 strands.

A097553

Number of positive words of length n in the monoid Br_6 of positive braids on 7 strands.

Terms

    a(0) =1a(1) =6a(2) =27a(3) =101a(4) =346a(5) =1131a(6) =3611a(7) =11396a(8) =35761a(9) =111906a(10) =349700a(11) =1092039a(12) =3409031a(13) =10640179a(14) =33206991a(15) =103631414a(16) =323402952a(17) =1009233980a(18) =3149469548a(19) =9828376731a(20) =30670834516a(21) =95712596642a(22) =298684343689a(23) =932085486213

External references