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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 11 |
| 5 | 30 |
| 6 | 96 |
| 7 | 298 |
| 8 | 1028 |
| 9 | 3485 |
| 10 | 12724 |
| 11 | 45705 |
| 12 | 173541 |
| 13 | 650298 |
| 14 | 2544692 |
| 15 | 9844616 |
| 16 | 39436571 |
| 17 | 156427321 |
| 18 | 638580481 |
| 19 | 2584305014 |
| 20 | 10714655777 |
| 21 | 44081695845 |
| 22 | 185148725201 |
| 23 | 772276053413 |
| 24 | 3279498523275 |
| 25 | 13839450883147 |
| 26 | 59326871290544 |
| 27 | 252873214965116 |
| 28 | 1092926867474669 |
| 29 | 4698994759995838 |
[1,1,2,4,11,30,96,298,1028,3485,12724,45705, 173541,650298,2544692,9844616,39436571,156427321, 638580481,2584305014,10714655777,44081695845, 185148725201,772276053413,3279498523275, 13839450883147,59326871290544,252873214965116, 1092926867474669,4698994759995838] |