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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 26 |
| 5 | 110 |
| 6 | 532 |
| 7 | 2541 |
| 8 | 12644 |
| 9 | 63024 |
| 10 | 318857 |
| 11 | 1618947 |
| 12 | 8277062 |
| 13 | 42453073 |
| 14 | 218597485 |
| 15 | 1128527057 |
| 16 | 5841301830 |
| 17 | 30297014746 |
| 18 | 157442596130 |
| 19 | 819511659381 |
| 20 | 4272054888643 |
| 21 | 22299423992018 |
| 22 | 116539878029773 |
| 23 | 609718298887977 |
| 24 | 3193136462042241 |
| 25 | 16737951567806110 |
[1,2,6,26,110,532,2541,12644,63024,318857,1618947, 8277062,42453073,218597485,1128527057,5841301830, 30297014746,157442596130,819511659381, 4272054888643,22299423992018,116539878029773, 609718298887977,3193136462042241, 16737951567806110] |