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| n | a(n) |
|---|---|
| 3 | 13 |
| 4 | 114 |
| 5 | 672 |
| 6 | 3334 |
| 7 | 15030 |
| 8 | 63978 |
| 9 | 261880 |
| 10 | 1043658 |
| 11 | 4076856 |
| 12 | 15688108 |
| 13 | 59650623 |
| 14 | 224625639 |
| 15 | 839026657 |
| 16 | 3112293273 |
| 17 | 11474908920 |
| 18 | 42080197859 |
| 19 | 153566261268 |
| 20 | 557943898644 |
| 21 | 2018901838589 |
| 22 | 7277784002970 |
| 23 | 26142839723154 |
| 24 | 93599166705077 |
| 25 | 334072869753357 |
[13,114,672,3334,15030,63978,261880,1043658, 4076856,15688108,59650623,224625639,839026657, 3112293273,11474908920,42080197859,153566261268, 557943898644,2018901838589,7277784002970, 26142839723154,93599166705077,334072869753357] |