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| n | a(n) |
|---|---|
| 0 | 3 |
| 1 | 26 |
| 2 | 163 |
| 3 | 894 |
| 4 | 4558 |
| 5 | 22196 |
| 6 | 104739 |
| 7 | 483062 |
| 8 | 2189530 |
| 9 | 9789900 |
| 10 | 43295118 |
| 11 | 189749676 |
| 12 | 825364668 |
| 13 | 3567219688 |
| 14 | 15332925731 |
| 15 | 65591312550 |
| 16 | 279415474594 |
| 17 | 1185903736412 |
| 18 | 5016725589402 |
| 19 | 21159849864964 |
| 20 | 89012979703940 |
[3,26,163,894,4558,22196,104739,483062,2189530, 9789900,43295118,189749676,825364668,3567219688, 15332925731,65591312550,279415474594, 1185903736412,5016725589402,21159849864964, 89012979703940] |