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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 4 |
| 3 | 8 |
| 4 | 14 |
| 5 | 24 |
| 6 | 40 |
| 7 | 66 |
| 8 | 106 |
| 9 | 174 |
| 10 | 286 |
| 11 | 480 |
| 12 | 814 |
| 13 | 1412 |
| 14 | 2480 |
| 15 | 4476 |
| 16 | 8184 |
| 17 | 15230 |
| 18 | 28652 |
| 19 | 54488 |
| 20 | 104262 |
| 21 | 201266 |
| 22 | 390090 |
| 23 | 760234 |
| 24 | 1486030 |
| 25 | 2914492 |
| 26 | 5728506 |
| 27 | 11289420 |
| 28 | 22279222 |
| 29 | 44046072 |
| 30 | 87181188 |
| 31 | 172777354 |
| 32 | 342724456 |
| 33 | 680524908 |
| 34 | 1352154964 |
| 35 | 2688763324 |
[2,4,8,14,24,40,66,106,174,286,480,814,1412,2480, 4476,8184,15230,28652,54488,104262,201266,390090, 760234,1486030,2914492,5728506,11289420,22279222, 44046072,87181188,172777354,342724456,680524908, 1352154964,2688763324] |