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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 4 |
| 4 | 10 |
| 5 | 40 |
| 6 | 100 |
| 7 | 400 |
| 8 | 1000 |
| 9 | 4000 |
| 10 | 10000 |
| 11 | 40000 |
| 12 | 100000 |
| 13 | 400000 |
| 14 | 1000000 |
| 15 | 4000000 |
| 16 | 10000000 |
| 17 | 40000000 |
| 18 | 100000000 |
| 19 | 400000000 |
| 20 | 1000000000 |
| 21 | 4000000000 |
| 22 | 10000000000 |
| 23 | 40000000000 |
| 24 | 100000000000 |
| 25 | 400000000000 |
| 26 | 1000000000000 |
| 27 | 4000000000000 |
| 28 | 10000000000000 |
| 29 | 40000000000000 |
| 30 | 100000000000000 |
| 31 | 400000000000000 |
[0,1,4,10,40,100,400,1000,4000,10000,40000,100000, 400000,1000000,4000000,10000000,40000000, 100000000,400000000,1000000000,4000000000, 10000000000,40000000000,100000000000,400000000000, 1000000000000,4000000000000,10000000000000, 40000000000000,100000000000000,400000000000000] |