A077209 - OEIS

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A077209 as a simple table

n	a(n)
0	2
1	21
2	101
3	102
4	201
5	1001
6	1002
7	2001
8	10001
9	10002
10	20001
11	100001
12	100002
13	200001
14	1000001
15	1000002
16	2000001
17	10000001
18	10000002
19	20000001
20	100000001
21	100000002
22	200000001

[2,21,101,102,201,1001,1002,2001,10001,10002, 20001,100001,100002,200001,1000001,1000002, 2000001,10000001,10000002,20000001,100000001, 100000002,200000001]