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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 22 |
| 5 | 103 |
| 6 | 519 |
| 7 | 2656 |
| 8 | 13798 |
| 9 | 72005 |
| 10 | 377132 |
| 11 | 1978263 |
| 12 | 10387415 |
| 13 | 54569162 |
| 14 | 286758658 |
| 15 | 1507147669 |
| 16 | 7922014506 |
| 17 | 41642626111 |
| 18 | 218903934463 |
| 19 | 1150737770732 |
| 20 | 6049275496670 |
| 21 | 31800411817677 |
| 22 | 167171979847160 |
| 23 | 878810026664375 |
[1,2,5,22,103,519,2656,13798,72005,377132,1978263, 10387415,54569162,286758658,1507147669,7922014506, 41642626111,218903934463,1150737770732, 6049275496670,31800411817677,167171979847160, 878810026664375] |