Number of reduced words of length n in the Weyl group B_15.

Terms

a(0) =1a(1) =15a(2) =119a(3) =665a(4) =2939a(5) =10933a(6) =35580a(7) =103972a(8) =277950a(9) =689282a(10) =1602727a(11) =3523945a(12) =7376794a(13) =14784390a(14) =28500705a(15) =53054703a(16) =95687255a(17) =167682425a(18) =286219155a(19) =476896733a(20) =777117381a(21) =1240541355a(22) =1942863430a(23) =2989193690a(24) =4523359115a(25) =6739474341a(26) =9896158795a(27) =14333801669a(28) =20495294280