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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 12 |
| 4 | 58 |
| 5 | 318 |
| 6 | 1887 |
| 7 | 11772 |
| 8 | 75969 |
| 9 | 502554 |
| 10 | 3389059 |
| 11 | 23211411 |
| 12 | 161016948 |
| 13 | 1129004057 |
| 14 | 7988722083 |
| 15 | 56972470875 |
| 16 | 409085637498 |
| 17 | 2955030274440 |
| 18 | 21458933307618 |
| 19 | 156567620461329 |
| 20 | 1147179838787850 |
| 21 | 8437546788462108 |
| 22 | 62273149495359127 |
| 23 | 461053250613575613 |
| 24 | 3423339068045408289 |
[1,3,12,58,318,1887,11772,75969,502554,3389059, 23211411,161016948,1129004057,7988722083, 56972470875,409085637498,2955030274440, 21458933307618,156567620461329,1147179838787850, 8437546788462108,62273149495359127, 461053250613575613,3423339068045408289] |