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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 10 |
| 3 | 36 |
| 4 | 133 |
| 5 | 495 |
| 6 | 1846 |
| 7 | 6888 |
| 8 | 25705 |
| 9 | 95931 |
| 10 | 358018 |
| 11 | 1336140 |
| 12 | 4986541 |
| 13 | 18610023 |
| 14 | 69453550 |
| 15 | 259204176 |
| 16 | 967363153 |
| 17 | 3610248435 |
| 18 | 13473630586 |
| 19 | 50284273908 |
| 20 | 187663465045 |
| 21 | 700369586271 |
| 22 | 2613814880038 |
| 23 | 9754889933880 |
| 24 | 36405744855481 |
| 25 | 135868089488043 |
| 26 | 507066613096690 |
[1,3,10,36,133,495,1846,6888,25705,95931,358018, 1336140,4986541,18610023,69453550,259204176, 967363153,3610248435,13473630586,50284273908, 187663465045,700369586271,2613814880038, 9754889933880,36405744855481,135868089488043, 507066613096690] |