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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 18 |
| 3 | 218 |
| 4 | 2466 |
| 5 | 26282 |
| 6 | 269298 |
| 7 | 2685818 |
| 8 | 26269506 |
| 9 | 253202762 |
| 10 | 2413042578 |
| 11 | 22791125018 |
| 12 | 213710059746 |
| 13 | 1992110014442 |
| 14 | 18478745943858 |
| 15 | 170706760005818 |
| 16 | 1571545212141186 |
| 17 | 14425381885981322 |
| 18 | 132080236787517138 |
| 19 | 1206736529597136218 |
| 20 | 11004743954450081826 |
| 21 | 100195617094657583402 |
[1,2,18,218,2466,26282,269298,2685818,26269506, 253202762,2413042578,22791125018,213710059746, 1992110014442,18478745943858,170706760005818, 1571545212141186,14425381885981322, 132080236787517138,1206736529597136218, 11004743954450081826,100195617094657583402] |