a(1) = 1; a(n) = a(n-1) + Sum_{k=2..n} a(floor(n/k)).

Terms

a(0) =1a(1) =2a(2) =4a(3) =8a(4) =13a(5) =22a(6) =32a(7) =48a(8) =67a(9) =93a(10) =120a(11) =164a(12) =209a(13) =266a(14) =331a(15) =418a(16) =506a(17) =626a(18) =747a(19) =905a(20) =1076a(21) =1276a(22) =1477a(23) =1755a(24) =2039a(25) =2370a(26) =2723a(27) =3149a(28) =3576a(29) =4112