Number of necklace compositions of n with distinct differences.

Terms

a(0) =1a(1) =2a(2) =2a(3) =4a(4) =5a(5) =6a(6) =11a(7) =18a(8) =26a(9) =38a(10) =60a(11) =90a(12) =139a(13) =213a(14) =329a(15) =501a(16) =747a(17) =1144a(18) =1712a(19) =2548a(20) =3836a(21) =5732a(22) =8442a(23) =12654a(24) =18624