The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 2 |
| 3 | 4 |
| 4 | 20 |
| 5 | 40 |
| 6 | 200 |
| 7 | 202 |
| 8 | 400 |
| 9 | 2000 |
| 10 | 2002 |
| 11 | 2020 |
| 12 | 4000 |
| 13 | 20000 |
| 14 | 20002 |
| 15 | 20020 |
| 16 | 20200 |
| 17 | 40000 |
| 18 | 200000 |
| 19 | 200002 |
| 20 | 200020 |
| 21 | 200200 |
| 22 | 202000 |
| 23 | 400000 |
| 24 | 2000000 |
| 25 | 2000002 |
| 26 | 2000020 |
| 27 | 2000200 |
| 28 | 2002000 |
| 29 | 2020000 |
| 30 | 4000000 |
| 31 | 20000000 |
| 32 | 20000002 |
| 33 | 20000020 |
| 34 | 20000200 |
| 35 | 20000202 |
| 36 | 20002000 |
| 37 | 20002002 |
| 38 | 20020000 |
| 39 | 20200000 |
[0,2,4,20,40,200,202,400,2000,2002,2020,4000, 20000,20002,20020,20200,40000,200000,200002, 200020,200200,202000,400000,2000000,2000002, 2000020,2000200,2002000,2020000,4000000,20000000, 20000002,20000020,20000200,20000202,20002000, 20002002,20020000,20200000] |