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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 32 |
| 5 | 112 |
| 6 | 416 |
| 7 | 1595 |
| 8 | 6274 |
| 9 | 25167 |
| 10 | 102555 |
| 11 | 423339 |
| 12 | 1768311 |
| 13 | 7458501 |
| 14 | 31731885 |
| 15 | 136027943 |
| 16 | 587011854 |
| 17 | 2548351515 |
| 18 | 11122561784 |
| 19 | 48780963600 |
| 20 | 214886096297 |
| 21 | 950408168978 |
| 22 | 4218983830646 |
| 23 | 18792082175472 |
| 24 | 83964867542325 |
| 25 | 376248603204020 |
| 26 | 1690509753133442 |
| 27 | 7614571890623423 |
| 28 | 34378422957641746 |
[1,1,3,9,32,112,416,1595,6274,25167,102555,423339, 1768311,7458501,31731885,136027943,587011854, 2548351515,11122561784,48780963600,214886096297, 950408168978,4218983830646,18792082175472, 83964867542325,376248603204020,1690509753133442, 7614571890623423,34378422957641746] |