Palindromes of even length only using 0 or 1.

Terms

a(0) =0a(1) =11a(2) =1001a(3) =1111a(4) =100001a(5) =101101a(6) =110011a(7) =111111a(8) =10000001a(9) =10011001a(10) =10100101a(11) =10111101a(12) =11000011a(13) =11011011a(14) =11100111a(15) =11111111a(16) =1000000001a(17) =1000110001a(18) =1001001001a(19) =1001111001a(20) =1010000101a(21) =1010110101a(22) =1011001101a(23) =1011111101a(24) =1100000011a(25) =1100110011