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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 13 |
| 3 | 22 |
| 4 | 124 |
| 5 | 409 |
| 6 | 1921 |
| 7 | 8908 |
| 8 | 41933 |
| 9 | 204016 |
| 10 | 988083 |
| 11 | 4818956 |
| 12 | 23520912 |
| 13 | 114859013 |
| 14 | 561215577 |
| 15 | 2742234243 |
| 16 | 13400786521 |
| 17 | 65488989956 |
| 18 | 320045756818 |
| 19 | 1564085835402 |
| 20 | 7643812356261 |
| 21 | 37356003891307 |
| 22 | 182562316287946 |
[1,13,22,124,409,1921,8908,41933,204016,988083, 4818956,23520912,114859013,561215577,2742234243, 13400786521,65488989956,320045756818, 1564085835402,7643812356261,37356003891307, 182562316287946] |