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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 8 |
| 5 | 12 |
| 6 | 21 |
| 7 | 40 |
| 8 | 70 |
| 9 | 117 |
| 10 | 263 |
| 11 | 450 |
| 12 | 703 |
| 13 | 1385 |
| 14 | 2423 |
| 15 | 5501 |
| 16 | 8617 |
| 17 | 18249 |
| 18 | 29352 |
| 19 | 61970 |
| 20 | 103568 |
| 21 | 209309 |
| 22 | 404977 |
| 23 | 853279 |
| 24 | 1609502 |
| 25 | 3008915 |
| 26 | 5342983 |
| 27 | 10287184 |
| 28 | 19087437 |
| 29 | 38498011 |
| 30 | 78520137 |
| 31 | 145642314 |
[1,2,4,8,12,21,40,70,117,263,450,703,1385,2423, 5501,8617,18249,29352,61970,103568,209309,404977, 853279,1609502,3008915,5342983,10287184,19087437, 38498011,78520137,145642314] |