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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 28 |
| 5 | 96 |
| 6 | 349 |
| 7 | 1294 |
| 8 | 4900 |
| 9 | 19175 |
| 10 | 75820 |
| 11 | 304450 |
| 12 | 1237879 |
| 13 | 5080610 |
| 14 | 21057345 |
| 15 | 87889165 |
| 16 | 369769072 |
| 17 | 1565029070 |
| 18 | 6660413594 |
| 19 | 28504725054 |
| 20 | 122534388266 |
| 21 | 529047867652 |
| 22 | 2293336147592 |
| 23 | 9977416694579 |
| 24 | 43555434463046 |
| 25 | 190726313779884 |
| 26 | 837672138930133 |
| 27 | 3689004196873598 |
| 28 | 16287162984427420 |
[1,1,3,8,28,96,349,1294,4900,19175,75820,304450, 1237879,5080610,21057345,87889165,369769072, 1565029070,6660413594,28504725054,122534388266, 529047867652,2293336147592,9977416694579, 43555434463046,190726313779884,837672138930133, 3689004196873598,16287162984427420] |