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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 4 |
| 3 | 5 |
| 4 | 9 |
| 5 | 23 |
| 6 | 32 |
| 7 | 87 |
| 8 | 293 |
| 9 | 2138 |
| 10 | 6707 |
| 11 | 15552 |
| 12 | 22259 |
| 13 | 60070 |
| 14 | 82329 |
| 15 | 142399 |
| 16 | 509526 |
| 17 | 651925 |
| 18 | 29194226 |
| 19 | 29846151 |
| 20 | 118732679 |
| 21 | 148578830 |
| 22 | 267311509 |
| 23 | 683201848 |
| 24 | 950513357 |
| 25 | 2584228562 |
| 26 | 8703199043 |
| 27 | 63506621863 |
| 28 | 199223064632 |
| 29 | 461952751127 |
| 30 | 661175815759 |
[1,1,4,5,9,23,32,87,293,2138,6707,15552,22259, 60070,82329,142399,509526,651925,29194226, 29846151,118732679,148578830,267311509,683201848, 950513357,2584228562,8703199043,63506621863, 199223064632,461952751127,661175815759] |