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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 2 |
| 3 | 11 |
| 4 | 47 |
| 5 | 193 |
| 6 | 778 |
| 7 | 3118 |
| 8 | 12480 |
| 9 | 49929 |
| 10 | 199725 |
| 11 | 798911 |
| 12 | 3195656 |
| 13 | 12782636 |
| 14 | 51130558 |
| 15 | 204522247 |
| 16 | 818089003 |
| 17 | 3272356029 |
| 18 | 13089424134 |
| 19 | 52357696554 |
| 20 | 209430786236 |
| 21 | 837723144965 |
| 22 | 3350892579881 |
| 23 | 13403570319547 |
| 24 | 53614281278212 |
| 25 | 214457125112872 |
[0,2,11,47,193,778,3118,12480,49929,199725,798911, 3195656,12782636,51130558,204522247,818089003, 3272356029,13089424134,52357696554,209430786236, 837723144965,3350892579881,13403570319547, 53614281278212,214457125112872] |