Number of binary strings of length n with equal numbers of 0000 and 0011 substrings.

Terms

a(0) =1a(1) =2a(2) =4a(3) =8a(4) =14a(5) =25a(6) =46a(7) =83a(8) =151a(9) =278a(10) =510a(11) =940a(12) =1744a(13) =3242a(14) =6051a(15) =11346a(16) =21341a(17) =40285a(18) =76326a(19) =145065a(20) =276573a(21) =528901a(22) =1014219a(23) =1949950a(24) =3758249a(25) =7259903a(26) =14053760a(27) =27258744a(28) =52966596a(29) =103091048