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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 13 |
| 3 | 60 |
| 4 | 348 |
| 5 | 1916 |
| 6 | 10668 |
| 7 | 59257 |
| 8 | 329350 |
| 9 | 1830234 |
| 10 | 10171315 |
| 11 | 56525022 |
| 12 | 314128014 |
| 13 | 1745708992 |
| 14 | 9701463927 |
| 15 | 53914132251 |
| 16 | 299618062228 |
| 17 | 1665073290365 |
| 18 | 9253344266757 |
| 19 | 51423790446062 |
| 20 | 285778433090830 |
| 21 | 1588162056821687 |
| 22 | 8825923956549044 |
| 23 | 49048479247236561 |
[1,1,13,60,348,1916,10668,59257,329350,1830234, 10171315,56525022,314128014,1745708992,9701463927, 53914132251,299618062228,1665073290365, 9253344266757,51423790446062,285778433090830, 1588162056821687,8825923956549044, 49048479247236561] |