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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 11 |
| 4 | 34 |
| 5 | 103 |
| 6 | 306 |
| 7 | 901 |
| 8 | 2636 |
| 9 | 7685 |
| 10 | 22372 |
| 11 | 65111 |
| 12 | 189590 |
| 13 | 552547 |
| 14 | 1612154 |
| 15 | 4709369 |
| 16 | 13773368 |
| 17 | 40329465 |
| 18 | 118217992 |
| 19 | 346891115 |
| 20 | 1018872626 |
| 21 | 2995250535 |
| 22 | 8812601062 |
| 23 | 25948130525 |
| 24 | 76456539156 |
| 25 | 225427875325 |
| 26 | 665066293480 |
[1,4,11,34,103,306,901,2636,7685,22372,65111, 189590,552547,1612154,4709369,13773368,40329465, 118217992,346891115,1018872626,2995250535, 8812601062,25948130525,76456539156,225427875325, 665066293480] |