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| n | a(n) |
|---|---|
| 1 | 8 |
| 2 | 18 |
| 3 | 21 |
| 4 | 160 |
| 5 | 1590 |
| 6 | 2420 |
| 7 | 18620 |
| 8 | 69229 |
| 9 | 83790 |
| 10 | 279964 |
| 11 | 494520 |
| 12 | 598810 |
| 13 | 676450 |
| 14 | 1183147 |
| 15 | 4233720 |
| 16 | 5600348 |
| 17 | 14217074 |
| 18 | 20025836 |
| 19 | 64278677 |
| 20 | 425208387 |
| 21 | 604048830 |
| 22 | 750851470 |
| 23 | 1981942354 |
[8,18,21,160,1590,2420,18620,69229,83790,279964, 494520,598810,676450,1183147,4233720,5600348, 14217074,20025836,64278677,425208387,604048830, 750851470,1981942354] |