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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 9 |
| 3 | 34 |
| 4 | 141 |
| 5 | 621 |
| 6 | 2849 |
| 7 | 13467 |
| 8 | 65127 |
| 9 | 320686 |
| 10 | 1602294 |
| 11 | 8103087 |
| 12 | 41397186 |
| 13 | 213331026 |
| 14 | 1107604764 |
| 15 | 5788249329 |
| 16 | 30422897664 |
| 17 | 160717169622 |
| 18 | 852894534042 |
| 19 | 4544635033164 |
| 20 | 24305345593290 |
| 21 | 130423538829518 |
| 22 | 701994030831654 |
| 23 | 3788979493701069 |
| 24 | 20503322609731348 |
[1,3,9,34,141,621,2849,13467,65127,320686,1602294, 8103087,41397186,213331026,1107604764,5788249329, 30422897664,160717169622,852894534042, 4544635033164,24305345593290,130423538829518, 701994030831654,3788979493701069, 20503322609731348] |