The number of idempotents in the Jones (or Temperley-Lieb) monoid on the set [1..n].

A225798

The number of idempotents in the Jones (or Temperley-Lieb) monoid on the set [1..n].

Terms

    a(0) =1a(1) =2a(2) =5a(3) =12a(4) =36a(5) =96a(6) =311a(7) =886a(8) =3000a(9) =8944a(10) =31192a(11) =96138a(12) =342562a(13) =1083028a(14) =3923351a(15) =12656024a(16) =46455770a(17) =152325850a(18) =565212506a(19) =1878551444a(20) =7033866580a(21) =23645970022a(22) =89222991344a(23) =302879546290

External references