Total number of runs of 1's in all length n binary words in which 1's occur in runs of at least 3.

Terms

a(0) =0a(1) =0a(2) =1a(3) =3a(4) =6a(5) =10a(6) =17a(7) =31a(8) =58a(9) =106a(10) =188a(11) =328a(12) =570a(13) =990a(14) =1715a(15) =2957a(16) =5074a(17) =8674a(18) =14787a(19) =25149a(20) =42676a(21) =72260a(22) =122104a(23) =205952a(24) =346804a(25) =583100a(26) =979013a(27) =1641575a(28) =2749150a(29) =4598730