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| n | a(n) |
|---|---|
| 0 | 2 |
| 1 | 7 |
| 2 | 22 |
| 3 | 69 |
| 4 | 216 |
| 5 | 671 |
| 6 | 2066 |
| 7 | 6313 |
| 8 | 19180 |
| 9 | 58035 |
| 10 | 175110 |
| 11 | 527357 |
| 12 | 1586144 |
| 13 | 4766599 |
| 14 | 14316154 |
| 15 | 42981201 |
| 16 | 129009108 |
| 17 | 387158363 |
| 18 | 1161737198 |
| 19 | 3485735845 |
| 20 | 10458256072 |
| 21 | 31376865327 |
| 22 | 94134790242 |
| 23 | 282412759289 |
| 24 | 847255055036 |
[2,7,22,69,216,671,2066,6313,19180,58035,175110, 527357,1586144,4766599,14316154,42981201, 129009108,387158363,1161737198,3485735845, 10458256072,31376865327,94134790242,282412759289, 847255055036] |