Number of binary strings of length n with no substrings equal to 0000, 0110, or 1111.

Terms

a(0) =1a(1) =2a(2) =4a(3) =8a(4) =13a(5) =22a(6) =36a(7) =59a(8) =97a(9) =160a(10) =263a(11) =433a(12) =712a(13) =1172a(14) =1928a(15) =3173a(16) =5220a(17) =8590a(18) =14133a(19) =23256a(20) =38264a(21) =62962a(22) =103596a(23) =170461a(24) =280475a(25) =461501a(26) =759354a(27) =1249456a(28) =2055862a(29) =3382748