Number of binary words of length n containing at least one subword 101 and no subword 11.

Terms

a(0) =0a(1) =0a(2) =0a(3) =1a(4) =2a(5) =4a(6) =8a(7) =15a(8) =27a(9) =48a(10) =84a(11) =145a(12) =248a(13) =421a(14) =710a(15) =1191a(16) =1989a(17) =3309a(18) =5487a(19) =9073a(20) =14966a(21) =24634a(22) =40472a(23) =66384a(24) =108729a(25) =177858a(26) =290610a(27) =474364a(28) =773615a(29) =1260643