Even nonnegative integers in base 2 (bisection of A007088).

Terms

a(0) =0a(1) =10a(2) =100a(3) =110a(4) =1000a(5) =1010a(6) =1100a(7) =1110a(8) =10000a(9) =10010a(10) =10100a(11) =10110a(12) =11000a(13) =11010a(14) =11100a(15) =11110a(16) =100000a(17) =100010a(18) =100100a(19) =100110a(20) =101000a(21) =101010a(22) =101100a(23) =101110a(24) =110000a(25) =110010a(26) =110100a(27) =110110a(28) =111000a(29) =111010