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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 3 |
| 6 | 6 |
| 7 | 10 |
| 8 | 20 |
| 9 | 38 |
| 10 | 75 |
| 11 | 145 |
| 12 | 288 |
| 13 | 571 |
| 14 | 1147 |
| 15 | 2304 |
| 16 | 4652 |
| 17 | 9413 |
| 18 | 19133 |
| 19 | 38999 |
| 20 | 79753 |
| 21 | 163489 |
| 22 | 335996 |
| 23 | 692028 |
| 24 | 1428351 |
| 25 | 2953637 |
| 26 | 6118456 |
| 27 | 12694486 |
| 28 | 26377235 |
| 29 | 54881902 |
| 30 | 114333228 |
| 31 | 238460819 |
| 32 | 497883758 |
| 33 | 1040572232 |
| 34 | 2176812874 |
| 35 | 4557723208 |
| 36 | 9550565627 |
| 37 | 20028241000 |
| 38 | 42030974050 |
[1,1,1,2,3,6,10,20,38,75,145,288,571,1147,2304, 4652,9413,19133,38999,79753,163489,335996,692028, 1428351,2953637,6118456,12694486,26377235, 54881902,114333228,238460819,497883758,1040572232, 2176812874,4557723208,9550565627,20028241000, 42030974050] |