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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 23 |
| 5 | 70 |
| 6 | 231 |
| 7 | 747 |
| 8 | 2519 |
| 9 | 8596 |
| 10 | 30022 |
| 11 | 104652 |
| 12 | 372171 |
| 13 | 1327738 |
| 14 | 4795592 |
| 15 | 17329563 |
| 16 | 63304887 |
| 17 | 231602170 |
| 18 | 853989048 |
| 19 | 3150826452 |
| 20 | 11704071278 |
| 21 | 43519371188 |
| 22 | 162687329027 |
| 23 | 608474865891 |
| 24 | 2286424185195 |
| 25 | 8597775368680 |
| 26 | 32455844916962 |
| 27 | 122568464638204 |
| 28 | 464459733245576 |
| 29 | 1760989548140200 |
[1,1,3,8,23,70,231,747,2519,8596,30022,104652, 372171,1327738,4795592,17329563,63304887, 231602170,853989048,3150826452,11704071278, 43519371188,162687329027,608474865891, 2286424185195,8597775368680,32455844916962, 122568464638204,464459733245576,1760989548140200] |