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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 13 |
| 4 | 75 |
| 5 | 471 |
| 6 | 3273 |
| 7 | 26916 |
| 8 | 262027 |
| 9 | 2851375 |
| 10 | 33353433 |
| 11 | 422098711 |
| 12 | 5947420449 |
| 13 | 94264842933 |
| 14 | 1637995975164 |
| 15 | 29950444958268 |
| 16 | 558160521126939 |
| 17 | 10427042476673645 |
| 18 | 194220965933772135 |
| 19 | 3611256888560663173 |
| 20 | 67328916459842949045 |
| 21 | 1266687562134302300334 |
| 22 | 24238971105618591823339 |
[1,3,13,75,471,3273,26916,262027,2851375,33353433, 422098711,5947420449,94264842933,1637995975164, 29950444958268,558160521126939,10427042476673645, 194220965933772135,3611256888560663173, 67328916459842949045,1266687562134302300334, 24238971105618591823339] |