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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 10 |
| 3 | 62 |
| 4 | 233 |
| 5 | 2621 |
| 6 | 21519 |
| 7 | 174970 |
| 8 | 1556367 |
| 9 | 13214094 |
| 10 | 114946790 |
| 11 | 994170593 |
| 12 | 8597453449 |
| 13 | 74512061062 |
| 14 | 645033668224 |
| 15 | 5586152757889 |
| 16 | 48378422171047 |
| 17 | 418955799991860 |
| 18 | 3628283346449943 |
| 19 | 31421658477126927 |
| 20 | 272119104488034718 |
[0,10,62,233,2621,21519,174970,1556367,13214094, 114946790,994170593,8597453449,74512061062, 645033668224,5586152757889,48378422171047, 418955799991860,3628283346449943, 31421658477126927,272119104488034718] |