a(1) = 1 thereafter a(n) = Sum_{k=1..n-1} ceiling(a(n-k)/k).

Terms

a(0) =1a(1) =1a(2) =2a(3) =4a(4) =7a(5) =12a(6) =21a(7) =34a(8) =55a(9) =88a(10) =143a(11) =227a(12) =361a(13) =572a(14) =908a(15) =1439a(16) =2279a(17) =3607a(18) =5709a(19) =9033a(20) =14294a(21) =22615a(22) =35779a(23) =56605a(24) =89551a(25) =141671a(26) =224123a(27) =354561a(28) =560908a(29) =887349