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Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A209930 as a simple table

na(n)
11
211
3101
41111
510111
6101111
71011001
81100101
910010101
1010011101
1110100011
1210101101
1310110011
1410111001
1511000111
1611100101
1711110111
1811111101
19100100111
20100111001
21101001001
22101001011
23101100011
24101101111
25101111011
26101111111
27110010101

[1,11,101,1111,10111,101111,1011001,1100101,
 10010101,10011101,10100011,10101101,10110011,
 10111001,11000111,11100101,11110111,11111101,
 100100111,100111001,101001001,101001011,101100011,
 101101111,101111011,101111111,110010101]