a(n) = Sum_{k=1..n} mu(k) * 2^(n - k).

Terms

a(0) =0a(1) =1a(2) =1a(3) =1a(4) =2a(5) =3a(6) =7a(7) =13a(8) =26a(9) =52a(10) =105a(11) =209a(12) =418a(13) =835a(14) =1671a(15) =3343a(16) =6686a(17) =13371a(18) =26742a(19) =53483a(20) =106966a(21) =213933a(22) =427867a(23) =855733a(24) =1711466a(25) =3422932a(26) =6845865a(27) =13691730a(28) =27383460a(29) =54766919