Number of compositions (ordered partitions) of n where the gcd of the part sizes is not 1.

Terms

a(0) =0a(1) =1a(2) =1a(3) =2a(4) =1a(5) =5a(6) =1a(7) =8a(8) =4a(9) =17a(10) =1a(11) =38a(12) =1a(13) =65a(14) =19a(15) =128a(16) =1a(17) =284a(18) =1a(19) =518a(20) =67a(21) =1025a(22) =1a(23) =2168a(24) =16a(25) =4097a(26) =256a(27) =8198a(28) =1a(29) =16907