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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 6 |
| 4 | 9 |
| 5 | 17 |
| 6 | 31 |
| 7 | 50 |
| 8 | 87 |
| 9 | 167 |
| 10 | 302 |
| 11 | 528 |
| 12 | 992 |
| 13 | 1907 |
| 14 | 3518 |
| 15 | 6539 |
| 16 | 12645 |
| 17 | 24327 |
| 18 | 46006 |
| 19 | 88361 |
| 20 | 172240 |
| 21 | 332882 |
| 22 | 641385 |
| 23 | 1249453 |
| 24 | 2441841 |
| 25 | 4748632 |
| 26 | 9252605 |
| 27 | 18128340 |
| 28 | 35506424 |
| 29 | 69433187 |
| 30 | 136116163 |
| 31 | 267424477 |
| 32 | 525052400 |
| 33 | 1030970356 |
| 34 | 2027883854 |
[1,2,4,6,9,17,31,50,87,167,302,528,992,1907,3518, 6539,12645,24327,46006,88361,172240,332882,641385, 1249453,2441841,4748632,9252605,18128340,35506424, 69433187,136116163,267424477,525052400,1030970356, 2027883854] |