Number of reduced words of length n in the Weyl group A_27.

Terms

a(0) =1a(1) =27a(2) =377a(3) =3626a(4) =26999a(5) =165852a(6) =874755a(7) =4071079a(8) =17052724a(9) =65259715a(10) =230856472a(11) =761987905a(12) =2364726003a(13) =6943746516a(14) =19395654894a(15) =51770913911a(16) =132567002957a(17) =326758146932a(18) =777583981286