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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 22 |
| 2 | 275 |
| 3 | 2574 |
| 4 | 19943 |
| 5 | 134618 |
| 6 | 816596 |
| 7 | 4543396 |
| 8 | 23522279 |
| 9 | 114532572 |
| 10 | 528773278 |
| 11 | 2329635750 |
| 12 | 9845310101 |
| 13 | 40080724376 |
| 14 | 157739993037 |
| 15 | 601928809878 |
| 16 | 2232820512417 |
| 17 | 8069089487932 |
| 18 | 28463636262974 |
| 19 | 98170848275720 |
| 20 | 331548644228131 |
| 21 | 1097891113532048 |
| 22 | 3568885868192419 |
[1,22,275,2574,19943,134618,816596,4543396, 23522279,114532572,528773278,2329635750, 9845310101,40080724376,157739993037,601928809878, 2232820512417,8069089487932,28463636262974, 98170848275720,331548644228131,1097891113532048, 3568885868192419] |