Number of 1-dimensional sandpiles with n grains piling up against the wall.

Terms

a(0) =1a(1) =1a(2) =1a(3) =2a(4) =3a(5) =5a(6) =9a(7) =14a(8) =24a(9) =40a(10) =67a(11) =112a(12) =186a(13) =312a(14) =520a(15) =868a(16) =1449a(17) =2417a(18) =4034a(19) =6730a(20) =11229a(21) =18735a(22) =31254a(23) =52143a(24) =86989a(25) =145119a(26) =242096a(27) =403871a(28) =673751a(29) =1123964