Number of binary strings of length n with equal numbers of 0000 and 1111 substrings.

Terms

a(0) =1a(1) =2a(2) =4a(3) =8a(4) =14a(5) =26a(6) =48a(7) =88a(8) =164a(9) =302a(10) =562a(11) =1044a(12) =1946a(13) =3632a(14) =6796a(15) =12738a(16) =23932a(17) =45044a(18) =84976a(19) =160610a(20) =304222a(21) =577358a(22) =1097974a(23) =2092018a(24) =3993784a(25) =7638400a(26) =14635854a(27) =28092662a(28) =54015016a(29) =104027610