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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 4 |
| 4 | 19 |
| 5 | 26 |
| 6 | 219 |
| 7 | 664 |
| 8 | 902 |
| 9 | 2109 |
| 10 | 2972 |
| 11 | 2982 |
| 12 | 9002 |
| 13 | 21009 |
| 14 | 29696 |
| 15 | 90002 |
| 16 | 210009 |
| 17 | 223114 |
| 18 | 292967 |
| 19 | 669024 |
| 20 | 900002 |
| 21 | 942997 |
| 22 | 2100009 |
| 23 | 2109664 |
| 24 | 2219779 |
| 25 | 8972876 |
| 26 | 9000002 |
| 27 | 21000009 |
| 28 | 21037924 |
| 29 | 21117304 |
| 30 | 21152824 |
| 31 | 21155344 |
| 32 | 28867722 |
| 33 | 29802897 |
| 34 | 29857886 |
| 35 | 90000002 |
[0,1,4,19,26,219,664,902,2109,2972,2982,9002, 21009,29696,90002,210009,223114,292967,669024, 900002,942997,2100009,2109664,2219779,8972876, 9000002,21000009,21037924,21117304,21152824, 21155344,28867722,29802897,29857886,90000002] |