Number of coverings of {1...n} by translation of a single set.

Terms

a(0) =1a(1) =2a(2) =3a(3) =6a(4) =11a(5) =22a(6) =45a(7) =92a(8) =188a(9) =382a(10) =791a(11) =1632a(12) =3357a(13) =6922a(14) =14289a(15) =29542a(16) =61013a(17) =126142a(18) =260664a(19) =538850a(20) =1113372a(21) =2300954a(22) =4752279a(23) =9814226a(24) =20257082a(25) =41798206a(26) =86204773a(27) =177729712a(28) =366231907a(29) =754356336