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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 10 |
| 3 | 35 |
| 4 | 132 |
| 5 | 524 |
| 6 | 2145 |
| 7 | 8924 |
| 8 | 37693 |
| 9 | 161604 |
| 10 | 701218 |
| 11 | 3068181 |
| 12 | 13515463 |
| 13 | 59931900 |
| 14 | 267372422 |
| 15 | 1198695390 |
| 16 | 5395604431 |
| 17 | 24377747242 |
| 18 | 110533789419 |
| 19 | 502767066982 |
| 20 | 2293016680176 |
| 21 | 10483543994331 |
| 22 | 48042092202958 |
| 23 | 220635526540888 |
| 24 | 1015233950976577 |
| 25 | 4679668922908784 |
| 26 | 21606351450045311 |
[1,3,10,35,132,524,2145,8924,37693,161604,701218, 3068181,13515463,59931900,267372422,1198695390, 5395604431,24377747242,110533789419,502767066982, 2293016680176,10483543994331,48042092202958, 220635526540888,1015233950976577,4679668922908784, 21606351450045311] |