Number of strict compositions of n with all adjacent parts (x, y) satisfying x <= 2y and y <= 2x.

Terms

a(0) =1a(1) =1a(2) =1a(3) =3a(4) =1a(5) =3a(6) =5a(7) =5a(8) =3a(9) =11a(10) =9a(11) =11a(12) =17a(13) =15a(14) =29a(15) =39a(16) =31a(17) =39a(18) =65a(19) =57a(20) =107a(21) =127a(22) =149a(23) =155a(24) =187a(25) =265a(26) =293a(27) =419a(28) =523a(29) =571