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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 14 |
| 4 | 81 |
| 5 | 521 |
| 6 | 3554 |
| 7 | 25172 |
| 8 | 183129 |
| 9 | 1359863 |
| 10 | 10264359 |
| 11 | 78521474 |
| 12 | 607449380 |
| 13 | 4744167924 |
| 14 | 37355679904 |
| 15 | 296232263792 |
| 16 | 2363773540473 |
| 17 | 18965408058723 |
| 18 | 152910824717297 |
| 19 | 1238260516988018 |
| 20 | 10066874219853977 |
| 21 | 82134185988563049 |
| 22 | 672294915226393926 |
| 23 | 5519252917557226452 |
[1,3,14,81,521,3554,25172,183129,1359863,10264359, 78521474,607449380,4744167924,37355679904, 296232263792,2363773540473,18965408058723, 152910824717297,1238260516988018, 10066874219853977,82134185988563049, 672294915226393926,5519252917557226452] |