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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 5 |
| 6 | 55 |
| 7 | 373 |
| 8 | 393 |
| 9 | 666 |
| 10 | 787 |
| 11 | 939 |
| 12 | 7997 |
| 13 | 53235 |
| 14 | 55255 |
| 15 | 55655 |
| 16 | 57675 |
| 17 | 506605 |
| 18 | 1801081 |
| 19 | 2215122 |
| 20 | 3826283 |
| 21 | 3866683 |
| 22 | 5051505 |
| 23 | 5226225 |
| 24 | 5259525 |
| 25 | 5297925 |
| 26 | 5614165 |
| 27 | 5679765 |
| 28 | 53822835 |
| 29 | 623010326 |
| 30 | 954656459 |
| 31 | 51717171715 |
[0,1,2,3,5,55,373,393,666,787,939,7997,53235, 55255,55655,57675,506605,1801081,2215122,3826283, 3866683,5051505,5226225,5259525,5297925,5614165, 5679765,53822835,623010326,954656459,51717171715] |