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| n | a(n) |
|---|---|
| 1 | 20 |
| 2 | 957 |
| 3 | 10132 |
| 4 | 56890 |
| 5 | 223320 |
| 6 | 695135 |
| 7 | 1837752 |
| 8 | 4302612 |
| 9 | 9168780 |
| 10 | 18124865 |
| 11 | 33696300 |
| 12 | 59523022 |
| 13 | 100692592 |
| 14 | 164133795 |
| 15 | 259075760 |
| 16 | 397577640 |
| 17 | 595133892 |
| 18 | 871360197 |
| 19 | 1250765060 |
| 20 | 1763612130 |
| 21 | 2446878280 |
| 22 | 3345312487 |
| 23 | 4512600552 |
[20,957,10132,56890,223320,695135,1837752,4302612, 9168780,18124865,33696300,59523022,100692592, 164133795,259075760,397577640,595133892,871360197, 1250765060,1763612130,2446878280,3345312487, 4512600552] |