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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 14 |
| 5 | 43 |
| 6 | 142 |
| 7 | 495 |
| 8 | 1794 |
| 9 | 6683 |
| 10 | 25388 |
| 11 | 97852 |
| 12 | 381406 |
| 13 | 1500317 |
| 14 | 5947798 |
| 15 | 23739795 |
| 16 | 95326150 |
| 17 | 384845581 |
| 18 | 1561220986 |
| 19 | 6361205709 |
| 20 | 26021379044 |
| 21 | 106826116871 |
| 22 | 439987835410 |
| 23 | 1817594141822 |
| 24 | 7529012424286 |
| 25 | 31265738342993 |
[1,1,2,5,14,43,142,495,1794,6683,25388,97852, 381406,1500317,5947798,23739795,95326150, 384845581,1561220986,6361205709,26021379044, 106826116871,439987835410,1817594141822, 7529012424286,31265738342993] |