Number of compositions of n where each pair of adjacent parts is relatively prime.

Terms

a(0) =1a(1) =1a(2) =2a(3) =4a(4) =7a(5) =14a(6) =25a(7) =48a(8) =90a(9) =168a(10) =316a(11) =594a(12) =1116a(13) =2096a(14) =3935a(15) =7388a(16) =13877a(17) =26061a(18) =48944a(19) =91919a(20) =172623a(21) =324188a(22) =608827a(23) =1143390a(24) =2147309a(25) =4032677a(26) =7573426a(27) =14223008a(28) =26711028a(29) =50163722