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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 23 |
| 3 | 47 |
| 4 | 237 |
| 5 | 766 |
| 6 | 3324 |
| 7 | 15186 |
| 8 | 56870 |
| 9 | 234074 |
| 10 | 1011095 |
| 11 | 4133704 |
| 12 | 17000454 |
| 13 | 71053058 |
| 14 | 295453260 |
| 15 | 1223130039 |
| 16 | 5077714327 |
| 17 | 21113301094 |
| 18 | 87637341300 |
| 19 | 363724250504 |
| 20 | 1510870009169 |
| 21 | 6274481387942 |
| 22 | 26050726753999 |
| 23 | 108178878898716 |
[3,23,47,237,766,3324,15186,56870,234074,1011095, 4133704,17000454,71053058,295453260,1223130039, 5077714327,21113301094,87637341300,363724250504, 1510870009169,6274481387942,26050726753999, 108178878898716] |