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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 9 |
| 5 | 13 |
| 6 | 20 |
| 7 | 43 |
| 8 | 80 |
| 9 | 326 |
| 10 | 775 |
| 11 | 3894 |
| 12 | 5629 |
| 13 | 7103 |
| 14 | 10523 |
| 15 | 61005 |
| 16 | 355588 |
| 17 | 1124509 |
| 18 | 1824015 |
| 19 | 2052357 |
| 20 | 2719588 |
| 21 | 5241202 |
| 22 | 10253662 |
| 23 | 17480124 |
| 24 | 42664033 |
| 25 | 83470664 |
| 26 | 282411553 |
| 27 | 328711697 |
| 28 | 432040721 |
| 29 | 1247136427 |
| 30 | 4461350728 |
| 31 | 15082139743 |
[1,2,4,9,13,20,43,80,326,775,3894,5629,7103,10523, 61005,355588,1124509,1824015,2052357,2719588, 5241202,10253662,17480124,42664033,83470664, 282411553,328711697,432040721,1247136427, 4461350728,15082139743] |