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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 10 |
| 4 | 38 |
| 5 | 164 |
| 6 | 783 |
| 7 | 4005 |
| 8 | 21400 |
| 9 | 117602 |
| 10 | 659019 |
| 11 | 3748736 |
| 12 | 21588796 |
| 13 | 125646501 |
| 14 | 737977155 |
| 15 | 4369147468 |
| 16 | 26048215099 |
| 17 | 156249597852 |
| 18 | 942344615209 |
| 19 | 5710710976884 |
| 20 | 34756875588376 |
| 21 | 212361179832431 |
| 22 | 1302068876523950 |
| 23 | 8009024360554817 |
| 24 | 49407447276951470 |
| 25 | 305609996146288873 |
| 26 | 1895015255546957578 |
[1,3,10,38,164,783,4005,21400,117602,659019, 3748736,21588796,125646501,737977155,4369147468, 26048215099,156249597852,942344615209, 5710710976884,34756875588376,212361179832431, 1302068876523950,8009024360554817, 49407447276951470,305609996146288873, 1895015255546957578] |