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

Terms

a(0) =1a(1) =3a(2) =0a(3) =8a(4) =3a(5) =-3a(6) =-10a(7) =22a(8) =22a(9) =12a(10) =1a(11) =-23a(12) =-36a(13) =-50a(14) =-35a(15) =93a(16) =76a(17) =76a(18) =57a(19) =17a(20) =38a(21) =16a(22) =-7a(23) =-103a(24) =-103a(25) =-129a(26) =-129a(27) =-185a(28) =-214a(29) =-184