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| n | a(n) |
|---|---|
| 1 | 70 |
| 2 | 210 |
| 3 | 518 |
| 4 | 1554 |
| 5 | 4006 |
| 6 | 12018 |
| 7 | 32006 |
| 8 | 96018 |
| 9 | 261670 |
| 10 | 785010 |
| 11 | 2173958 |
| 12 | 6521874 |
| 13 | 18267046 |
| 14 | 54801138 |
| 15 | 154764806 |
| 16 | 464294418 |
| 17 | 1319524390 |
| 18 | 3958573170 |
| 19 | 11307598598 |
| 20 | 33922795794 |
| 21 | 97317170086 |
| 22 | 291951510258 |
| 23 | 840713542406 |
| 24 | 2522140627218 |
[70,210,518,1554,4006,12018,32006,96018,261670, 785010,2173958,6521874,18267046,54801138, 154764806,464294418,1319524390,3958573170, 11307598598,33922795794,97317170086,291951510258, 840713542406,2522140627218] |