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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 31 |
| 5 | 113 |
| 6 | 443 |
| 7 | 1787 |
| 8 | 7445 |
| 9 | 31593 |
| 10 | 136351 |
| 11 | 596187 |
| 12 | 2636015 |
| 13 | 11763569 |
| 14 | 52920569 |
| 15 | 239731317 |
| 16 | 1092632909 |
| 17 | 5006816043 |
| 18 | 23053197067 |
| 19 | 106601983853 |
| 20 | 494856940025 |
| 21 | 2305237337415 |
| 22 | 10772988573393 |
| 23 | 50491926308985 |
[1,3,9,31,113,443,1787,7445,31593,136351,596187, 2636015,11763569,52920569,239731317,1092632909, 5006816043,23053197067,106601983853,494856940025, 2305237337415,10772988573393,50491926308985] |