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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 21 |
| 3 | 84 |
| 4 | 331 |
| 5 | 1300 |
| 6 | 5111 |
| 7 | 20144 |
| 8 | 79611 |
| 9 | 315420 |
| 10 | 1252351 |
| 11 | 4980904 |
| 12 | 19837091 |
| 13 | 79086740 |
| 14 | 315557991 |
| 15 | 1259856864 |
| 16 | 5032285771 |
| 17 | 20107685260 |
| 18 | 80366302031 |
| 19 | 321271760024 |
| 20 | 1284506433651 |
| 21 | 5136283390980 |
| 22 | 20539905484471 |
| 23 | 82143935602384 |
| 24 | 328528679208731 |
| 25 | 1313973518843900 |
| 26 | 5255470464625311 |
| 27 | 21020610992695944 |
[1,5,21,84,331,1300,5111,20144,79611,315420, 1252351,4980904,19837091,79086740,315557991, 1259856864,5032285771,20107685260,80366302031, 321271760024,1284506433651,5136283390980, 20539905484471,82143935602384,328528679208731, 1313973518843900,5255470464625311, 21020610992695944] |