List of binary words of lengths 0, 1, 2, etc., including empty word, each prefixed by a 2.

Terms

a(0) =2a(1) =20a(2) =21a(3) =200a(4) =201a(5) =210a(6) =211a(7) =2000a(8) =2001a(9) =2010a(10) =2011a(11) =2100a(12) =2101a(13) =2110a(14) =2111a(15) =20000a(16) =20001a(17) =20010a(18) =20011a(19) =20100a(20) =20101a(21) =20110a(22) =20111a(23) =21000a(24) =21001a(25) =21010a(26) =21011a(27) =21100a(28) =21101a(29) =21110