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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 7 |
| 5 | 19 |
| 6 | 63 |
| 7 | 229 |
| 8 | 955 |
| 9 | 4407 |
| 10 | 22445 |
| 11 | 124249 |
| 12 | 746003 |
| 13 | 4821287 |
| 14 | 33394193 |
| 15 | 246652725 |
| 16 | 1935828995 |
| 17 | 16086138151 |
| 18 | 141100295557 |
| 19 | 1302780182449 |
| 20 | 12630092274099 |
| 21 | 128275445380247 |
| 22 | 1362029496267529 |
| 23 | 15090795795916493 |
| 24 | 174167341456580947 |
| 25 | 2090520625244752407 |
[1,1,2,3,7,19,63,229,955,4407,22445,124249,746003, 4821287,33394193,246652725,1935828995,16086138151, 141100295557,1302780182449,12630092274099, 128275445380247,1362029496267529, 15090795795916493,174167341456580947, 2090520625244752407] |