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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 4 |
| 3 | 5 |
| 4 | 15 |
| 5 | 22 |
| 6 | 67 |
| 7 | 98 |
| 8 | 275 |
| 9 | 436 |
| 10 | 1249 |
| 11 | 1940 |
| 12 | 5244 |
| 13 | 8632 |
| 14 | 23896 |
| 15 | 38408 |
| 16 | 101419 |
| 17 | 170896 |
| 18 | 462361 |
| 19 | 760400 |
| 20 | 1975160 |
| 21 | 3383392 |
| 22 | 9001276 |
| 23 | 15054368 |
| 24 | 38623130 |
| 25 | 66984256 |
| 26 | 175903414 |
| 27 | 298045760 |
| 28 | 757228832 |
| 29 | 1326151552 |
| 30 | 3446259592 |
[1,1,4,5,15,22,67,98,275,436,1249,1940,5244,8632, 23896,38408,101419,170896,462361,760400,1975160, 3383392,9001276,15054368,38623130,66984256, 175903414,298045760,757228832,1326151552, 3446259592] |