a(n) is the number of base-4 n-digit numbers requiring only binary digits in bases 3 and 4.

Terms

a(0) =2a(1) =1a(2) =0a(3) =3a(4) =6a(5) =3a(6) =0a(7) =5a(8) =12a(9) =11a(10) =0a(11) =5a(12) =12a(13) =0a(14) =0a(15) =5a(16) =0a(17) =0a(18) =0a(19) =48a(20) =14a(21) =0a(22) =61a(23) =188a(24) =83a(25) =0a(26) =81a(27) =232a(28) =268a(29) =0