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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 4 |
| 4 | 5 |
| 5 | 15 |
| 6 | 20 |
| 7 | 57 |
| 8 | 77 |
| 9 | 218 |
| 10 | 295 |
| 11 | 835 |
| 12 | 1130 |
| 13 | 3199 |
| 14 | 4329 |
| 15 | 12256 |
| 16 | 16585 |
| 17 | 46955 |
| 18 | 63540 |
| 19 | 179893 |
| 20 | 243433 |
| 21 | 689202 |
| 22 | 932635 |
| 23 | 2640455 |
| 24 | 3573090 |
| 25 | 10116051 |
| 26 | 13689141 |
| 27 | 38756384 |
| 28 | 52445525 |
| 29 | 148482575 |
| 30 | 200928100 |
| 31 | 568863057 |
| 32 | 769791157 |
| 33 | 2179415178 |
| 34 | 2949206335 |
[1,1,4,5,15,20,57,77,218,295,835,1130,3199,4329, 12256,16585,46955,63540,179893,243433,689202, 932635,2640455,3573090,10116051,13689141,38756384, 52445525,148482575,200928100,568863057,769791157, 2179415178,2949206335] |