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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 10 |
| 5 | 43 |
| 6 | 216 |
| 7 | 1308 |
| 8 | 9157 |
| 9 | 73299 |
| 10 | 659701 |
| 11 | 6597228 |
| 12 | 72569509 |
| 13 | 870835456 |
| 14 | 11320860929 |
| 15 | 158492062165 |
| 16 | 2377380932700 |
| 17 | 38038094996499 |
| 18 | 646647614940484 |
| 19 | 11639657069589711 |
| 20 | 221153484322204510 |
| 21 | 4423069686450687468 |
| 22 | 92884463415464445994 |
| 23 | 2043458195140290381379 |
| 24 | 46999538488226678771718 |
[1,1,3,10,43,216,1308,9157,73299,659701,6597228, 72569509,870835456,11320860929,158492062165, 2377380932700,38038094996499,646647614940484, 11639657069589711,221153484322204510, 4423069686450687468,92884463415464445994, 2043458195140290381379,46999538488226678771718] |