The sum over all bitstrings b of length n with at least two runs of the number of runs in b not immediately followed by a longer run.

A208903

The sum over all bitstrings b of length n with at least two runs of the number of runs in b not immediately followed by a longer run.

Terms

    a(0) =0a(1) =4a(2) =12a(3) =32a(4) =76a(5) =180a(6) =412a(7) =940a(8) =2108a(9) =4700a(10) =10364a(11) =22716a(12) =49404a(13) =106876a(14) =229884a(15) =492284a(16) =1049596a(17) =2229756a(18) =4720636a(19) =9964540a(20) =20975612a(21) =44046332a(22) =92282876a(23) =192950268a(24) =402669564a(25) =838885372a(26) =1744863228a(27) =3623927804a(28) =7516258300a(29) =15569354748

External references