Number of base pyramids in all length n left factors of Dyck paths.

Terms

a(0) =0a(1) =0a(2) =1a(3) =1a(4) =4a(5) =5a(6) =14a(7) =20a(8) =49a(9) =76a(10) =175a(11) =286a(12) =637a(13) =1078a(14) =2353a(15) =4081a(16) =8788a(17) =15521a(18) =33098a(19) =59279a(20) =125476a(21) =227239a(22) =478192a(23) =873885a(24) =1830270a(25) =3370029a(26) =7030570a(27) =13027729a(28) =27088870a(29) =50469889