a(n) is the number of binary strings of length n which contain exactly one run of 1s of even length.

A384497

a(n) is the number of binary strings of length n which contain exactly one run of 1s of even length.

Terms

    a(0) =0a(1) =0a(2) =1a(3) =2a(4) =6a(5) =12a(6) =28a(7) =56a(8) =119a(9) =236a(10) =479a(11) =940a(12) =1859a(13) =3612a(14) =7028a(15) =13538a(16) =26051a(17) =49820a(18) =95098a(19) =180774a(20) =342944a(21) =648648a(22) =1224517a(23) =2306338a(24) =4336449a(25) =8138516a(26) =15250965a(27) =28535528a(28) =53320792a(29) =99504804

External references